WO2025031576A1 - New perfumes and uses thereof - Google Patents

Abstract

The present invention relates to new 4-(3',8',8'-trimethyl-2',3',4',7',8',8a'-hexahydro-1H-3a',7'-methanoazulen-6'-yl)butan-2-one, optionally methoxy-substituted at positions C-1 and C-3, of formula (I) as defined herein, and to the use thereof as ambergris-like perfumes. In particular, the present invention relates to the use of compounds (1), (2) and (3) as perfumes and as fixatives, and to the use thereof in perfume compositions in combination with other perfumes. The present invention also relates to a method for perfuming a product with the compounds according to the invention and to a corresponding perfumed product.

Description

Munich, August 8, 2023 Our reference: SM 6787-01 WO SOE/MCL

Applicant: Symrise AG

Official file number: New registration

Symrise AG

Mühlenfeldstraße 1 , 37603 Holzminden,

New fragrances and their uses

The present invention relates to new 4-(3',8',8'-trimethyl-2',3',4',7',8',8a'-hexahydro-1/7-3a',7'-methanoazulen-6'-yl)butan-2-ones of the formula (I) as defined herein, which are optionally methoxy-substituted at position C-1 and C-3, and to their use as amber-like fragrances. In particular, the present invention relates to the use of compounds (1), (2) and (3) as fragrances and as fixatives and to their use in fragrance compositions in combination with other fragrances. The present invention further relates to a process for perfuming a product with the compounds according to the invention and to a corresponding perfumed product.

'Gray ambergris' or 'ambergris' from the French “ambre gris" was already highly sought after by the coastal inhabitants of the Indian Ocean around 1000 BC because of its unusual smell, its great rarity and its supposed aphrodisiac properties and was worth its weight in gold (G. Ohloff, Irdische Düfte - Himmlische Lust - Eine Kulturgeschichte der Duftstoffe, Birkhäuser Verlag, Basel/Boston/Berlin, 1992, pp. 137-139). The first evidence of the use of ambergris in perfumery comes from Ibn Chordadhbeh (* around 820; f around 912), a geographer and administrative official from Dschibal in western Persia. As early as the ninth century, Arab sailors brought ambergris from the Near and Far East, North Africa and India to Europe (G. Ohloff, 'The Fragrance of Ambergris', in ET Theimer, Fragrance Chemistry - The Science of the Sense of Smell, Academic Press, Orlando, 1982, pp. 535-573). The light to dark gray, waxy substance is a pathological metabolic product of the sperm whale (Physeter macrocephalus L.), which is mechanical injury to the digestive tract caused by sharp-edged objects, it forms a kind of scab and is later excreted in lumps of 15-150 kg. Through oxidative aging processes in the sea under the influence of sunlight, it develops over the years a typical exotic-marine, dry-woody-tobacco-like smell of high substantivity and fixative adhesive power. This highly complex smell has aspects of:

1. Wet mossy forest floor. 2. Dried tobacco leaves. 3. Balsamic-creamy sandalwood. 4. Warm-animal alder wood. 5. Seaweed and sea water. 6. Feces (G. Ohloff, 'Chemistry of odorous and flavoring substances', in A. Davison, MJS Dewar, K. Hafner, E. Heilbronner, U. Hofmann, K. Niedenzu, K. Schäfer, G. Wittig (eds.), F. Boschke (writing), Advances in chemical research, Springer Verlag, Heidelberg, 1969, Vol. 12, Issue 2, p. 185).

Ambroxide (-)-Ambrein (+)-e ÄCoprosterol

Ysamber K Ambrocenide Ambrostar Belambre This special woody-dry, warm-balsamic and marine-tobacco-like amber profile of creamy-animal tonality and high originality, which made natural amber the most precious fragrance in perfumery, is found in perfect balance in ambroxide (alternative trade names: Ambrox, Amboxan, Ambrofix, Ambermore, Cetalor), the natural odorous principle of ambergris, in which it only occurs as a trace component at <0.3%. Ambroxide has been semi-synthetically accessible since the 1950s from sclareol, an ingredient of clary sage, and is now also biotechnologically and via cyclization using squalene-hopene cyclase (G. Ohloff, W. Pickenhagen, P. Kraft, F. Grau, Scent and Chemistry - The Molecular World of Odors, Wiley- VCH, Weinheim, 2022, p. 243). The excellent fixative properties of natural ambergris are explained by its content of (+)-ep/-coprosterol (20-40%) and (-)-ambrein (25-45%), the latter of which is also used to form ambroxide in nature. If natural ambergris or (-)-ambrein isolated from it is still used today - and this is only the case in a very small number of niche fragrances - it is solely due to these fixative properties. Due to the low content of natural ambroxide and also due to hygiene concerns and the price, natural ambergris no longer plays a role in commercial fine perfumery, as consumers are used to much higher doses of ambroxide from semi-synthetic sources. Ambroxide has therefore now lost its exclusivity, which can also be seen in the price drop from > 1200 €/kg in the 1980s to today below 200 €/kg in the 2020s.

In addition to the typical amber odor profile of ambroxide, ketals have recently played a major role. These have amber-like notes that lie somewhere between amber and alder wood (fungal-infected wood of the species Aquilaria malaccensis, Aquilaria crassna, Aquilaria microcarpa or Aquilaria filariä), i.e. more metallic-mineral than tobacco-balsamic-marine and, above all, much drier in their wood character and, instead of mossy-warm, a sharp animal sweetness that is sometimes perceived as pungent. The first of these amber-like ketals was amber ketal or Jeger's ketal, named after its inventor, ETH professor Oskar Jeger, who discovered it in 1952 during degradation studies of the manool from Halocarpus biformis (Hook.) Quinn. Although perceived as very intense by some people, it has a high anosmia rate, meaning that it is odorless for many others. Other amber-like ketals are spirambrene (1986) with additional spicy-aldehyde accents, karanal (1987) with candle wax-like nuances and hints of hot tar, as well as okoumal (1992) and ysamber K (1993). With the exception of ysamber K as an ethylene glycol ketal, these highly substituted ketals are not biodegradable and karanal was even the first fragrance to be classified as a fragrance because of its high Persistence and very high bioaccumulation (vPvB, Article 57e) has been classified as a substance of very high concern (SVHC - Substances of very high concern) by the ECHA (European Chemicals Agency). From August 27, 2023, Karanal may no longer be used in the EU. There is therefore a great need for novel amber-like fragrances without a ketal function but with similar amber-like odor properties to these amber ketals in order to serve the trend for these dry-woody, mineral-metallic amber-like notes that have dominated masculine perfumery since "1 Million" (2008) and "Invictus" (2013).

This trend was initiated by highly potent amber bodies such as ambrocenide (W. Pickenhagen, D. Schatkowski, for Dragoco, Eur. Pat. Appl. EP 857,723 A1 , 12.08.1998), which is itself a ketal and not biodegradable, but is so intense that the environmental impact is relatively small. Its success and its sustainable synthesis from cedrene led to a wave of new highly intense amber bodies in the industry, such as Ambrostar (E. Dilk, M. Eh, H. Surburg, US 2012/0077722 A1 , 28.09.2011), the more substantive and better fixing 2-pentanone derivative of ambrocenide, and Belambre from camphor (J. A. Ba- jgrowicz, EP761664 A1). These high-impact ambraketals reduced environmental exposure and, in the case of Ambrostar, they also brought improved fixative properties in the application forms, but they are still ketals with all their problematic properties, especially bioaccumulation.

It was therefore an object of the present invention to provide new amber-like odorants which have an amber-like odor as well as fixative properties and, in contrast to the previous odorants of this odor family, are not ketals.

wobei X und Y = H oder -OMe, und Surprisingly, a narrow family of optionally C-1 or C-3 methoxy-substituted 2-butanones of general formula (I) has now been identified.

where X and Y = H or -OMe, and

X = H if Y = -OMe, and

Y = H if X = -OMe or

X = Y = H, found that have the interesting and very typical amber-like smells of the previously mentioned amber ketals and have very good fixative properties without being ketals themselves. The substituent in position C-4 is derived from the renewable sesquiterpene cedrene.

wobei X und Y = H oder -OMe, und The above-defined problem is therefore solved by a compound or a mixture of compounds of formula (I) including all stereoisomers,

where X and Y = H or -OMe, and

X = H if Y = -OMe, and

Y = H if X = -OMe or

X = Y = H.

The compounds of formula (I) are amber-like fragrances that are also able to fix amber notes of other fragrances, i.e. to extend and modify their adhesion. The compounds can therefore be advantageously integrated into a range of fragrance mixtures and are suitable for a wide range of applications in different products. In addition, the compounds are more polar due to the oxygen substituents, so that they show low bioaccumulation.

Furthermore, the present invention relates to the use of a compound or mixture of compounds as defined above as a fragrance, in particular as an amber-like fragrance and/or for enhancing and/or modifying an amber-like and/or agarwood note of other fragrances and/or as a fixative, in particular for prolonging the adhesion of an amber-like and/or agarwood note of other fragrances. In the context of the present invention, amber-like fragrances are those fragrances that lie between amber and alder wood (fungal-infected wood of the species Aquilaria malaccensis, Aquilaria crassna, Aquilaria microcarpa or Aquilaria filariä). Compared to amber, they are more metallic-mineral rather than tobacco-like-balsamic-marine and, above all, much drier in their woody character and, instead of mossy-warm in their initial smell, they often have a sharp, animalistic sweetness that is almost perceived as pungent.

In the context of the present invention, a fixative is understood to mean a substance that is capable of prolonging the adhesion of odor notes of other fragrances, i.e. ensuring a longer-lasting fragrance in a product.

verwendet wird, um eine ambraartige und/oder Adlerholz-Note zu vermitteln, zu verstärken, zu modifizieren und/oder zu fixieren. The present invention further relates to the use of a compound as described above, wherein compound (1)

used to convey, enhance, modify and/or fix an amber and/or agarwood note.

Compared to an amber note, an agarwood note is much more animalistic and balsamic-sweet in its woody character. In addition to the sharp animal sweetness that is sometimes perceived as stinging, it is characterized by complementary spicy-bitter facets.

The present invention also relates to the use of a compound as described above, wherein compound (2)

verwendet wird, um eine holzige, ambraartige, Adlerholz-, pfefferige und/oder grüne Note zu vermitteln, zu verstärken, zu modifizieren und/oder zu fixieren. Ferner betrifft die vorliegende Erfindung auch die Verwendung einer Verbindung wie oben beschrieben, wobei Verbindung (3)

verwendet wird, um eine holzige, ambraartige oder Adlerholz-, pfefferige und/oder grüne Note zu vermitteln, zu verstärken, zu modifizieren und/oder zu fixieren.

is used to impart, enhance, modify and/or fix a woody, amber-like, agarwood, peppery and/or green note. Furthermore, the present invention also relates to the use of a compound as described above, wherein compound (3)

used to convey, enhance, modify and/or fix a woody, ambery or agarwood, peppery and/or green note.

In addition to the dry, woody amber and agarwood-like main character and the fixative properties common to all representatives, compounds (1)-(3) convey, strengthen or modify additional, different secondary notes. Compound (1) underlines dark, sweet, warm animal and tobacco-like accents, so that it harmonizes particularly well with balsamic-creamy sandalwood fragrances, while the Compound (2) vibrates more like musk, has an erogenous and clean effect, which highlights fresh, hesperidic-citric notes, which are further enhanced by the green-mossy touch. Compound (3), on the other hand, underlines soft, warm, spicy fragrance components with its transparent incense and pepper character and thus harmonizes particularly well with sour, fruity fragrance components.

According to a further aspect, the present invention relates to a fragrance composition comprising or consisting of a compound or mixture of compounds as defined above, in particular comprising compound (1), compound (2) and/or compound (3), and one or more further fragrance(s).

A fragrance composition according to the invention may contain any of the compounds (1) to (3) alone or two of the compounds (1) to (3) or all of the compounds (1) to (3) in combination.

The presence of compounds (1), (2) and/or (3) has a beneficial effect on fragrance compositions, as can be seen from the application examples below. In particular, the combination with amber or agarwood fragrances brings beneficial effects.

In particular, the present invention therefore relates to a fragrance composition as described above comprising or consisting of compound (1), compound (2) and/or compound (3) and at least one amber or agarwood fragrance.

Particularly preferred is the combination of one of the compounds (1), (2) or (3) with ambrocenide and/or ambrostar.

In a preferred embodiment of the fragrance composition as described above, the compounds (1), (2) and/or (3) each make up 0.001 to 10 wt.% of the fragrance composition, preferably 0.2 to 2 wt.%.

Also preferred is a fragrance composition as described above, wherein the amber fragrance(s) and/or agarwood fragrance(s) is/are selected from the group consisting of the stereoisomeric 2,2,5,8,8,9a-hexamethyloctahydro-4/7-4a,9-methanoazuleno[5,6-cf][1,3]dioxole, 2,5,8,8,9a-pentamethyl-2-propyloctahydro-4/7-4a,9-methanoazuleno[5,6-cf][1,3]dioxole, 2,5,8,8,9a-pentamethyl-2-(prop-1-en-1-yl)octahydro-4/7-4a,9-methanoazuleno[5,6-cf][1,3]dioxole, 2-(Methoxymethyl)-2,5,8,8,9a-pentamethyloctahydro-4/7-4a,9-methanoazuleno[5,6-cf][1,3]dioxole, 2,4-Dimethyl-2- (5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)-1,3-dioxolane, 2',2',3,7,7-pentamethylspiro[bicyclo[4.1,0]heptane-2,5'-[1,3]dioxane], 2'-isopropyl-1,7,7-trimethyl- spiro[bicyclo[2.2.1]heptane-2,4'-[1,3]dioxane], 1-(2',2',6'-trimethylcyclohexyl)hexan-3-ol, 2-methyl-5-(5',5',6'-trimethylbicyclo[2.2.1 hept-2'-yl)cyclohexanone, decahydro-

2,2, 6, 6,7,8, 8-heptamethyl-2/7-indeno[4,5-b]furane, 6,7-dihydro-1,1,2,3,3-pentamethyl-4(5/-/)-indanone, 1 a,3,3,4,6,6-hexamethyl-1 a,2,3,4,5,6,7,7a-octahydronaphtho[2,3-b]oxirene, 7,7,8,9,9-pentamethyl-4,4a,5,6,7,8,9,9b-octahydroindeno[4,5-cf][1,3]dioxins, 7,7,8,9,9-Pentamethyl-6,6a,7,8,9,9a-hexahydro-5/7-cyclopenta[h]quinazoline, 7, 7, 8, 9, 9-pentamethyl-6,7,8,9-tetrahydro-5/7-cyclopenta[h]quinazoline, 2,6,6,7,8,8-hexamethyldecahydro-2/7-indeno[4,5-b]furane, 2,2,6,6,7,8,8-heptamethyldecahydro-2/7-indeno[4,5- b]furane, 2,2,7,7,8,9,9-heptamethyldecahydroindeno[4,3a-b]furane, 7-methoxy-1,1,5,5-tetramethyl-1,3,4,5,6,7-hexahydro-2/7-2,4a-methanonaphthalene, 5,5-dimethyl-2-propyl- hexahydro-2/7-2,4a-methanonaphthalene-1 (5/-/)-one, 2,2,9, 11-tetramethylspiro[5.5]undec- 8-en-1-yl acetate, 3,8,8, 11 a-tetramethyldodecahydro-5/7-3,5a-epoxynapht[2,1-C]oxepine, 3a,6,6,9a-tetramethyl-1,2,3a,4,6,7,8,9,9a,9b-decahydronaphtho[2,1-b]furane and 3a,6,6,9a-tetramethyldodecahydronaphtho[2,1-b]furane as well as the reaction products from the acid-catalyzed cyclization of 1-(1 ’,6’-dimethyl-4’-(4”-methylpent-3”-en-1 ”-yl)cyclohex-3’-en-1 ’-yl)ethan-1-one.

According to a further aspect, the present invention also relates to a method for perfuming a product comprising the steps:

(i) providing a compound or mixture of compounds of formula (I) as defined above or a fragrance composition as defined above, and

(ii) adding the compound or mixture of compounds or the fragrance composition to the product to be perfumed, preferably in a sensorially effective amount, in particular in an amount sufficient to impart, enhance and/or modify an olfactory note.

A ‘sensory effective amount’ is an amount in which the compound or mixture of compounds or fragrance composition in the perfumed product can be perceived by a consumer compared to a product which does not contain the corresponding compound, mixture of compounds or fragrance composition. A process as described above is preferred, wherein in step (ii) compound (1) is added to the product to be perfumed in order to impart, enhance, modify and/or fix an amber-like and/or agarwood note and/or wherein compound (2) is added to the product to be perfumed in order to impart, enhance, modify and/or fix a woody, amber-like, agarwood, peppery and/or green note and/or wherein in step (ii) compound (3) is added to the product to be perfumed in order to impart, enhance, modify and/or fix a woody, amber-like, agarwood, peppery and/or green note.

Furthermore, the present invention relates to a perfumed product comprising a compound or mixture of compounds as defined above or a fragrance composition as described above.

A fragrance composition according to the invention is advantageously suitable for a wide range of applications in a wide variety of products.

Preferably, the perfumed product is selected from the group consisting of detergents and cleaning agents, hygiene and care products, preferably in the field of body and hair care, cosmetics and household, preferably selected from the group consisting of perfume extracts, eau de parfums, eau de toilettes, aftershave lotions, eau de colognes, pre-shave products, perfumed wet wipes, acidic, alkaline or neutral detergents, textile fresheners, ironing aids, liquid detergents, powdered detergents, laundry treatment agents, fabric softeners, laundry soaps, detergent tablets, disinfectants, surface disinfectants, air fresheners, aerosol sprays, waxes and varnishes, body care products, hand creams and lotions, foot creams and lotions, depilatory creams and lotions, aftershave creams and lotions, tanning creams and lotions, hair care products, deodorants, antiperspirants, decorative cosmetic products, candles, lamp oils, incense sticks, insecticides, repellents and propellants.

Even small amounts of the fragrance composition according to the invention in a product are sufficient to ensure a pleasant, long-lasting fragrance.

In a preferred embodiment of the product, the total amount of the fragrance composition is in a range of 0.05 to 5 wt.%, preferably 0.5 to 2 wt.%, each based on the total weight of the product.

In the following, the invention is described in more detail using some examples. Example 1: Preparation of 1-methoxy- and 3-methoxy-4-(3',8',8'-trimethyl- 2',3',4',7',8',8a'-hexahydro-1 'H-3a',7'-methanoazulen-6'-yl)butan-2-one by Claisen rearrangement

Synthesis of 1,2,2-trimethoxypropane

157 g (4.91 mol) of methanol, 600 mg (6.12 mmol) of sulfuric acid and 190 g (1.79 mol) of trimethyl orthoformate were placed at room temperature in a 1 liter three-necked flask with a magnetic stirrer, thermometer, reflux condenser and dropping funnel. 150 g (1.70 mol) of 1-methoxypropan-2-one were added dropwise over the course of 30 minutes, with the temperature rising to 50 °C. The mixture was then heated under reflux (52 °C) for 5 hours. The heating was removed, 3.50 g (33.7 mmol) of sodium carbonate were added to the mixture at room temperature and then fractionally distilled under vacuum in a 30 cm packed column with Raschig rings and column head. Yield: 204 g (89%) 1,2,2-trimethoxypropane (GC purity: 96%) as a colorless clear liquid.

GC-IR (GC purity 96%): v = 2994/2945/2838 (m), 1464 (w), 1381 (w), 1255 (w), 1136 (s), 1066 (m), 850 (w).

¹ H-NMR (400 MHz, CDCh): ö = 3.41 (s, 6 H, 2-MeO ₂ ), 3.37 (s, 3 H, 1-MeO), 3.23 (s, 1-H ₂ ), 1.35 (s, 3 H, 3-H3) ppm.

¹³ C-NMR (101 MHz, CDCh): ö = 100.0 (s, C-2), 74.1 (t, C-1), 59.3 (q, 1-MeO), 48.2/48.2 (2q, 2-MeO ₂ ), 20.1 (q, C-3) ppm.

GC-MS (70eV): m/z (%) = 41 (25), 43 (60), 45 (15), 47 (12), 53 (1), 57 (7), 71 (45), 89 (100), 103 (47), 119 (6).

Elimination of a methoxy group to the corresponding enol ether

82.0 g (0.61 mol) of the previously synthesized 1,2,2-trimethoxypropane, 1.00 g (12.6 mmol) of pyridine and 400 mg (4.08 mmol) of 85% phosphoric acid were placed in a 250 ml distillation apparatus with thermometer, magnetic stirrer, column (10 cm Raschig rings) and column head and heated under normal pressure. The mixture began to boil at 119 °C. At a reflux ratio of R:D = 25:1, a bottom temperature of 120-150 °C and a head temperature of 104-108 °C, 43.7 g of distillate were obtained (GC- Purity: 88%. Composition: 41% (E)-1,2-dimethoxyprop-1-ene, 17% (Z)-1,2-dimethoxyprop-1-ene, 30% 2,3-dimethoxyprop-1-ene).

GC-IR (GC purity 88%): v = 2998/2941/2839 (m), 1668 (w), 1625 (w), 1460 (w), 1220 (s), 1 136 (s), 1082 (m).

(E)-1,2-Dimethoxyprop-1-ene:

¹ H NMR (400 MHz, C _e D _e ): ö = 1.97 (d, J = 1.0 Hz, 3 H, 3-H ₃ ), 3.16 (s, 3 H, 2-MeO), 3.19 (s, 3 H, 1-MeO), 5.57 (q, J = 1.0 Hz, 1 H 1-H).

¹³ C NMR (101 MHz, C _e D _e ) ö = 14.1 (q, C-3), 54.8 (q, 2'-MeO), 59.8 (q, 1 '-MeO), 127.1 (d, C-1), 144.9 (s, C-2).

GC-MS (70eV): m/z (%) = 27 (8), 39 (9), 43 (48), 59 (100), 87 (84), 102 (90), 103 (5).

(Z)-1,2-Dimethoxyprop-1-ene:

¹ H NMR (400 MHz, CeDe): ö = 1.52 (d, J = 1.0 Hz, 3 H 3-H ₃ ), 3.14 (s, 3 H, 1-MeO), 3.62 (s, 3 H, 2-MeO), 5.08 (q, J = 1.0 Hz, 1 H, 1-H).

¹³ C NMR (101 MHz, CeDe) ö = 15.9 (q, C-3), 57.5 (q, 2'-MeO), 59.5 (q, 1'-MeO), 129.1 (d, C-1), 137.0 (s, C-2).

GC-MS (70eV): m/z (%) = 29 (32), 43 (53), 59 (99), 87 (95), 102 (100), 103 (5).

2,3-Dimethoxyprop-1-ene:

¹ H NMR (400 MHz, CeDe): ö = 3.13 (s, 3 H, 3-MeO), 3.20 (s, 3 H, 2-MeO), 3.81 (d, J = 1.0 Hz, 2 H, 3-H ₂ ), 3.96 (d, J = 2.0 Hz, 1 H, 1-Hb), 4.26 (dt, J = 2.0, 1.0 Hz, 1 H, 1-H _a ).

¹³ C NMR (101 MHz, CeDe) ö = 54.4 (q, 2'-MeO), 58.0 (q, 3'-MeO), 72.8 (t, C-3), 82.1 (t, C-1), 161.0 (s, C-2).

GC-MS (70eV): m/z (%) = 29 (19), 42 (38), 45 (38), 59 (13), 72 (100), 102 (9).

Preparation of 5-((1 ’,2’-Dimethoxypropan-2’-yl)oxy)-

3,8,8-trimethyl-6-methyleneoctahydro-1H-3a,7-methanoazulene

In a 25 ml three-necked flask stirred apparatus with magnetic stirrer, thermometer and reflux condenser, 2.00 g (9.09 mmol) of 3,8,8-trimethyl-6-methyleneoctahydro-1/7-3a,7-methanoazulen-5-ol, 8.00 g (78.4 mmol) of a mixture of 65% (E/Z)-1,2-dimethoxyprop-1-ene, 35% 2,3-dimethoxyprop-1-ene and 420 mg (7.00 mmol) of acetic acid were stirred under nitrogen atmosphere for 16 h at 90 °C. The heating was then removed. and the mixture was diluted with 20 ml of methyl tert-butyl ether at room temperature while stirring. It was washed twice with 20 ml of 5% sodium carbonate solution each time and then concentrated. The residue was treated with 10 ml of hexane while warm and then left to crystallize for 3 hours at 5 °C. The residue thus obtained was filtered off and the mother liquor was concentrated to give 2.00 g of crude product (GC purity: 48%, 33% crude yield). After column chromatography (Büchi PrepChrom C-700, 80 g silica gel 60, eluent: hexane/ethyl acetate = 99:1 — >95:5, 71 min, 20 ml/min at 20 ml per fraction, TLC: Rs = 0.44 (SiC>2 60, hexane/ethyl acetate = 10:1) 640 mg (22%) of the title compound were obtained (GC purity: 99%).

Eluting component: GC-IR (GC 34%, Thermo Nicolet 6700): v = 2949 (s) 1643 (w), 1463 (w), 1384 (w), 1131 (m), 1050 (m).

¹ H NMR (400 MHz, CDCh) ö = 0.83 - 0.88 (m, 3 H, 1 '-Me), 0.92 - 1 .00 (m, 6 H, 8'-Me ₂ ), 1 .23 - 1 .37 (m, 3 H, 2'-, 4'-, 9'-H _b ), 1 .37 - 1 .50 (m, 4 H, 3-Me, 1 '-Hb), 1.51 - 1 .64 (m, 1 H, 1 '-Ha), 1 .68 - 1 .80 (m, 2 H, 3'-H, 9'-H _a ), 1 .80 - 1 .91 (m, 2 H, 8a'-H, 2'-H _a ), 1 .91 - 2.07 (m, 1 H, 4'-H _a ), 2.34 (d, J = 4.5 Hz, 1 H, 7'-H), 3.33 (s, 3 H, 2-MeO), 3.34 - 3.39 (m, 4 H, 1- MeO, 1-Hb), 3.49 (d, J = 10.0 Hz, 1 H, 1-H _a ), 4.46 - 4.61 (m, 1 H, 5'-H), 4.68 - 4.77 (m, 1

H, HbC=C-6', exo-methylene), 5.04 (t, J = 2.5 Hz, 1 H, H _a C=C-6', exo-methylene).

¹³ C NMR (101 MHz, CDCh) ö = 15.4 (q, 3'-Me), 21 .9 (q, C-3), 25.9 (t, C-1 '), 26.1 / 26.8 (2q, 8'-Me), 36.9 (t, C-2'), 41 .7 (d, C-3'), 42.1 (s, C-8'), 43.7 (t, C-4'), 45.0 (t, C-9'), 49.6 (q, 3-MeO), 54.7 (s, C-3a'), 57.1 (d, C-8a'), 59.3 (q, 1-MeO), 60.9 (d, C-7'), 69.7 (d, C-5'), 75.8 (t, C-1), 101.1 (s, C-2), 107.6 (t, H ₂ C=C-6'), 152.3 (s, C-6').

GC/MS: m/z (%): 41 (21), 55 (9), 71 (51), 95 (18), 103 (100), 119 (24), 133 (14), 147 (22), 203 (34), 220 (7), 245 (4), 290 (1).

Final eluting component: GC-IR (GC 65%, Thermo Nicolet 6700): v = 2949 (s), 1644 (w), 1463 (w), 1384 (w), 1131 (m), 1050 (m).

¹ H NMR (400 MHz, CDCh) ö = 0.86 (m, 3H, 3'-Me), 0.92 - 1 .00 (m, 6 H, 8'-Me ₂ ), 1 .23 -

I .37 (m, 3 H, 2'-, 4'-, 9'-H _b ), 1 .37 - 1 .50 (m, 4 H, 3-Me, 1 '-Hb), 1 .51 - 1 .64 (m, 1 H, 1 ”-H _a ), 1 .68 - 1 .80 (m, 2 H, 3'-H, 9'-H _a ), 1 .80 - 1 .91 (m, 2 H, 2'-H _a , 8a'-H), 1 .91 - 2.07 (m, 1 H, 4'-H _a ), 2.34 (d, J = 4.5 Hz, 1 H, 7a'-H), 3.30 (s, 3 H, 2-MeO), 3.34 - 3.39 (m, 2 H, 1-H _b ), 3.41 (s, 3 H, 1-MeO), 3.54 (d, J = 10.0 Hz, 1 H 1-Ha), 4.46 - 4.61 (m, 1 H, 5'-H), 4.68 - 4.77 (m, 1 H, HbC=C-6'), 4.95 (t, J = 2.5 Hz, 1 H, H _a C=C-6'). ¹³ C NMR (101 MHz, CDCh) O = 15.5 (q, 3'-Me), 21 .1 (q, C-3), 25.9 (t, C-1 '), 26.2 / 26.8 (2 q, 8'-Me ₂ ), 36.9 (t, C-2'), 41 .7 (d, C-3'), 42.1 (s, C-8'), 43.4 (t, C-4'), 45.0 (t, C-9'), 49.2 (q, 3-MeO), 54.8 (s, C-3a'), 57.1 (d, C-8a'), 59.3 (q, 1-MeO), 60.8 (d, C-7'), 69.3 (d, C-5'), 75.1 (t, C-1), 101.1 (s, C-2), 107.6 (t, H ₂ C=C-6'), 152.4 (s, C-6'). m/z (%) = 41 (22), 55 (9), 71 (52), 95 (23), 103 (100), 119 (29), 133 (18), 147 (28), 203 (48), 220 (4), 290 (1).

Preparation of 3-methoxy-4-(3’,8’,8’-trimethyl-2’,3’,4’,7’,8’,8a’-hexahydro-1H-3a’,7’-methanoazulen-6-yl)butan-2-one and 1-methoxy-4-(3’,8’,8’-trimethyl-2’,3’,4’,7’,8’,8a’- hexahydro-1H-3a’,7’-methanoazulen-6’-yl)butan-2-one by Claisen rearrangement

1.50 g (4.66 mmol) of 5-((1',2'-dimethoxypropan-2'-yl)oxy)-3,8,8-trimethyl-6-methyleneoctahydro-1/7-3a,7-methanoazulene were heated in a Kugelrohr distillation apparatus (Büchi Glass Oven B-585) at 160 °C and 100 mbar for 4 h, after which the heating was removed. 1.09 g of crude product remained in the residue (GC purity: 78%). After column chromatography (Büchi PrepChrom C-700, 80 g silica gel 60, eluent: hexane/acetic ester = 98:2—>92:8, 71 min, 20 ml/min at 20 ml per fraction, TLC: Rs = 0.33 and 0.25 (SiO ₂ 60, hexane/acetic ester = 10:1) 38.0 mg 3-methoxy-4-(3',8',8'-trimethyl-2',3',4',7',8',8a'- hexahydro-1 /7-3a',7'-methanoazulen-6'-yl)butan-2-one (GC purity: 94%) and 513 mg 1- Methoxy-4-(3',8',8'-trimethyl-2',3',4',7',8',8a'-hexahydro-1/7-3a',7'-methanoazulen-6'-yl)butan-2-one (GC purity: 94%) was obtained.

3-Methoxy-4-(3’,8’,8’-trimethyl-2’,3’,4’,7’,8’,8a’-hexahydro-1H-3a’,7’-methanoazulene- 6’-yl)butan-2-one (1:1 mixture of two diastereomers, [Compound (1)])

GC-IR (GC purity 94%, Thermo Nicolet 6700): v = 2949/2901/2835 (s), 1729 (w), 1468 (w), 1358 (w), 1109 (m).

¹ H NMR (400 MHz, CDCh): ö = 0.83 / 0.84 (d, J = 7.0 Hz, 6 H, 3'-Me ₂ ), 0.96 / 1 .01 (2s, 12

H, 8'-Me ₄ ), 1 .28 - 1 .45 m, 6 H, (1 '-Hb, 2'-H _b , 9'-H _b ) ₂ ), 1 .53 - 1 .63 (m, 2 H, (1 '-H _a ) ₂ ), 1 .64 -

I .80 (m, 6 H, (3'-H, 8 _a '-H, 9'-H _a ) ₂ ), 1 .80 - 1 .88 (m, 4 H, (2'-H _a , 4'-H _b ) ₂ ), 1 .89 / 1 .90 (2s, 2 H, 7-H), 2.13 / 2.17 (2s, 6 H, (1-H ₃ ) ₂ ), 2.15 - 2.38 (m, 6 H, (4-H ₂ ) ₂ , (4'-H _a ) ₂ ), 3.34 / 3.35 (2s, 6 H, 3-MeO ₂ ), 3.65 (d, J = 7.0 Hz, 1 H, 3-H) / 3.62 - 3.72 (m, 1H, 3-H), 5.29 (dd, J = 4.0, 3.0 Hz, 1H, 5'-H) / 5.31 - 5.38 (m, 1H, 5'-H).

¹³ C NMR (100 MHz, CDCh): ö = 15.4 / 15.4 (2q, 3'-Me), 24.8 / 24.8 (2t, C-1 '), 25.0 / 25.4 (2q, C-1), 25.6 / 25.6 / 27.6 / 27.6 (4q, 8'-Me), 36.2 / 36.2 (2t, C-2'), 38.9 / 38.9 (t, C-4'), 40.5 / 40.5 / 40.6 / 40.7 (4t, C-4), 41.5 / 41.5 (2d, C-3'), 48.5 / 48.5 (2s, C-8'), 52.7 / 53.5 (2s, C-7'), 53.8 / 53.9 (2s, C-3a'), 57.9 / 58.5 (2q, 3-MeO), 59.1 / 59.2 (d, C-8a'), 86.3 / 87.1 (2d, C-3), 122.5 / 122.8 (2d, 5'=CH ₂ ), 139.2 / 139.4 (2s, C-6'), 210.8 / 211 .7 (2s, C-2).

MS (El): m/z (%): 43 (33), 55 (16), 69 (21), 79 (18), 91 (42), 105 (33), 1 19 (33), 131 (24), 147 (26), 159 (32), 173 (15), 187 (7), 203 (8), 215 (100), 247 (68), 258 (68), 275 (1), 290 (1).

Odor description: amber-like and dry woody-ambery, with animalic accents towards agarwood and cashmeran (1,1,2,3,3-pentamethyl-1,2,3,5,6,7-hexahydro-4/7-inden-4-one).

1-Methoxy-4-(3',8',8'-trimethyl-2',3',4',7',8',8a'-hexahydro-1H-3a',7'-methanoazulen-6'-yl)butan-2-one [Compound (2)]

GC-IR (GC purity 94%, Thermo Nicolet 6700): v = 2948 (s), 1732 (w), 1464 (w), 1110 (w).

¹ H NMR (600 MHz, CDCh): ö = 0.84 (d, J = 7.0 Hz, 3 H, 3'-Me), 0.95 / 1 .00 (2s, 6 H, (8'- Me) ₂ ), 1.31 - 1 .43 (m, 3 H, 1 '-,2'-,9'-H _a ), 1 .53 - 1 .62 (m, 1 H, 1 '-Hb), 1 .65 - 1 .71 (m, 2 H, 8a'-H, 9'-Hb), 1.71 - 1 .77 (m, 1 H 3'-H), 1 .78 - 1 .90 (m, 3 H, 2'-H _b , 4'-H _a , 7'-H), 2.12 - 2.21 (m, 2 H, 4'-Hb, 4-Ha), 2.27 - 2.36 (m, 1 H, 4-H _b ), 2.45 - 2.61 (m, 1 H, 3-H ₂ ), 3.42 (s, 3 H, 1- MeO), 4.02 (s, 2 H, 1-H ₂ ), 5.17 - 5.22 (m, 1H, 5'-H).

¹³ C NMR (151 MHz, CDCh): ö = 15.4 (q, 3'-Me), 24.8 (t, CT), 25.6 / 27.6 (2q, (8'-Me) ₂ ), 31 .3 (t, C-4), 36.1 (t, C-2'), 37.2 (t, C-3), 38.8 (t, C-4'), 40.7 (t, C-9'), 41 .4 (d, C-3'), 48.4 (s, C-8'), 53.5 (d, C-7'), 54.0 (s, C-3a'), 59.0 (d, C-8a'), 59.3 (q, 1-MeO), 77.7 (t, C-1), 119.1 (d, 5'= _CH2 ), 142.8 (s, C-6'), 208.6 (s, C-2).

MS (El): m/z (%) = 41 (44), 55 (32), 69 (100), 81 (24), 91 (28), 109 (34), 118 (32), 135 (39), 149 (15), 162 (30, 177 (25), 187 (13), 205 (10), 220 (10).

Odour description: dry, woody and ambery, reminiscent of ambrocenide (2,2,5,8,8,9a-hexamethyloctahydro-4/7-4a,9-methanoazuleno[5,6-c(][1,3]dioxol), with a peppery note reminiscent of rotundone ((3S,5R,8S)-3,4,5,6,7,8-hexahydro-3cr,8cr-dimethyl-5cr-(1-methyl-ethenyl)azulen-1(2/7)-one) and green nuances.

Example 2: Preparation of 4-(3',8',8'-trimethyl-2',3',4',7',8',8a'-hexahydro-1 'H-3a',7'-methanoazulen-6'-yl)butan-2-one by Claisen rearrangement Synthesis of 2-ethoxyprop-1-ene

In a 250 ml distillation apparatus equipped with a thermometer, magnetic stirrer, column (10 cm, Raschig rings) and column head, 100 g (758 mmol) of 2,2-diethoxypropane, 1.20 g (15.2 mmol) of pyridine and 500 mg (4.34 mmol) of 85% phosphoric acid were heated under normal pressure until the reaction mixture began to boil at 107 °C. At a reflux ratio of R:D = 10:1, a bottom temperature of 107-122 °C and a top temperature of 72-92 °C, 91.0 g (76%) of the title compound were isolated by distillation (GC purity: 55%).

GC-IR (Thermo Nicolet 6700): v = 3121/2990/2941 (m), 1657 (m), 1599 (w), 1449/1376 (m), 1283/1277 (s), 1098/1085 (s), 798 (m).

¹ H NMR (400 MHz, C _e D _e ) ö = 1 .08 (t, J = 7.0 Hz, 3H, 1 '-Me), 1 .79 (d, J = 1 .0 Hz, 3H C-3), 3.48 (q, J = 7.0 Hz, 2H, 1 '-H ₂ ), 3.83 (d, J = 1 .0 Hz, 1 H, 3-Hb), 3.89 (dq, J = 2.0, 1 .0 Hz, 1 H, 3-Ha).

¹³ C NMR (101 MHz, C _e D _e ) ö = 14.6 (q, C-2'), 21.2 (q, C-3), 62.7 (t, CT), 81 .3 (t, C-1), 160.1 (s, C-2).

GC-MS (70eV): m/z (%) = 29 (32), 39 (20), 43 (100), 58 (89), 86 (94).

5-((2'-Ethoxypropan-2'-yl)oxy)-3,8,8-trimethyl-6-methyleneoctahydro-1H-3a,7-methanoazulene

In a 10 ml one-neck flask equipped with a magnetic stirrer, thermometer and reflux condenser, 1.00 g (4.55 mmol) of 3,8,8-trimethyl-

6-methyleneoctahydro-1/7-3a,7-methanoazulen-5-ol, 5.00 g (58.1 mmol) 2-ethoxyprop-1-ene and 200 mg (3.33 mmol) acetic acid were stirred at 75 °C for 6 h. The heating was removed, the mixture was diluted with 50 ml methyl tert-butyl ether at room temperature while stirring, washed once with 20 ml 5% sodium carbonate solution and then evaporated to dryness on a rotary evaporator, whereby 1.10 g (79%) of product was isolated (GC purity: 80%).

GC-IR (Thermo Nicolet 6700): v = 2949/2919/2882 (s), 1645 (w), 1464 (w), 1384 (w), 1278 (w), 1204 (w), 1164 (w), 1050 (m).

¹ H NMR (400 MHz, C _e D _e ): ö = 0.87 (d, J = 7.0 Hz, 3 H, 3-Me), 0.90 / 1 .06 (s, 6 H, 8-Me ₂ ), 1.16 (t, J = 7.0 Hz, 3 H, 2”-H ₃ ), 1.22 - 1.31 (m, 1 H, 2-Hb), 1.32 - 1.39 (m, 2 H, 1-H _b , 9-Hb), 1 .41 / 1 .45 (2s, 6 H, 1 '-H ₃ , 3'-H ₃ ), 1 .46 - 1 .53 (m, 2 H, 1-H _a , 4-Hb), 1 .57 - 1 .67 (m, 1 H, 3- H), 1 .65 - 1 .74 (m, 1 H, 9-H _a ), 1 .74 - 1 .80 (m, 1 H, 2-H _a ), 1 .80 - 1 .89 (m, 1 H, 8a-H), 2.06 (ddd, J = 12.0, 7.5, 3.0 Hz, 1 H, 4-H _a ), 2.37 (d, J = 4.5 Hz, 1 H, 7-H), 3.46 (dq, J = 9.0, 7.0 Hz, 1 H, 1 ”-Hb), 3.60 (dq, J = 9.0, 7.0 Hz, 1 H, 1 ”-H _a ), 4.62 (ddt, J = 10.0, 7.5, 2.5 Hz, 1 H, 5-H), 4.88 / 5.29 (t, J = 3.0 Hz, 2 H, H ₂ C=C-6).

¹³ C NMR (101 MHz, C _e D _e ): ö = 15.8 (q, 3-Me), 15.8 (q, C-2”), 25.8 / 26.3 (2q, C-1 ', -3'), 26.2 (t, C-1), 26.4 / 27.0 (2q, 8-Me ₂ ), 37.2 (t, C-2), 42.0 (d, C-3), 42.3 (s, C-8), 44.0 (t, C-4), 45.6 (t, C-9), 55.2 (s, C-3a), 56.7 (t, C-1”), 57.4 (d, C-8a), 61.3 (d, C-7), 69.7 (d, C-5), 100.7 (s, C-2'), 108.0 (t, 5=CH ₂ ), 153.1 (s, C-6).

GC-MS (70eV): m/z (%) = 59 (39), 69 (4), 79 (2), 87 (100), 91 (5), 105 (3), 119 (4), 147 (3), 161 (2), 176 (3), 203 (3), 217 (2), 248 (2), 260 (2).

4-(3’,8’,8’-Trimethyl-2’,3’,4’,7’,8’,8a’-hexahydro-1 ’H-3a’,7’-methanoazulen-6’-yl)butan-2-one [Compound (3)]

1.10 g (2.88 mmol) of 5-((2-ethoxypropan-2-yl)oxy)-3,8,8-trimethyl-6-methyleneocta-hydro- 1 /7-3a,7-methanoazulene (GC purity 80%) were heated in a Kugelrohr distillation apparatus (Büchi Glass Oven B-585) for 4 h at 160 °C and 100 mbar. The heating was removed and the product was allowed to cool to room temperature, leaving 800 mg of crude product in the residue (GC purity 33%, 35% crude yield). After column chromatography (Büchi PrepChrom C-700, 80 g silica gel 60, eluent: hexane/ethyl acetate = 97:3—>92:8, 71 min, 20 ml/min at 20 ml per fraction, TLC: Rs = 0.20 (SiO ₂ 60, hexane/ethyl acetate = 20:1)) 240 mg (32%) of the title compound were obtained (GC purity 99%).

Odor description: dry-peppery, woody-amber-like, with clear aspects of cedar wood and black pepper, as well as a sour-spicy apple note in the initial smell.

GC-IR (Thermo Nicolet 6700): v = 2950/2908/2838 (s), 1732 (m), 1467 (w), 1363 (w), 1273 (w), 1221 (w), 1157 (w).

¹ H NMR (600 MHz, CDCh): ö = 0.84 (d, J = 7.0 Hz, 3 H, 3'-Me), 0.95 / 1 .00 (2s, 6 H, Me ₂ C- 8'), 1 .32 - 1 .42 (m, 3 H, 1 '-, 2'-, 9'-H _b ,), 1 .53 - 1 .61 (m, 1 H, 1 '-Ha), 1 .68 (ddd, J = 11 .0, 4.5, 1.5 Hz, 2 H, 8a'-H, 9'-H _a ), 1.71 - 1.78 (m, 1 H, 3'-H), 1.78 - 1.84 (m, 2 H, 4a'-H _b , 7'-H), 1 .84 - 1 .90 (m, 1 H, 2'-H _a ), 2.10 - 2.21 (m, 5 H, 1-H ₃ , 4-, 4'-H _b ), 2.24 - 2.35 (m, 1 H, 4-H _a ), 2.48 (ddd, J = 16.0, 9.5, 6.0 Hz, 1 H, 3-H _b ), 2.57 (ddd, J = 16.5, 10.0, 5.5 Hz, 1 H, 3-H _a ), 5.18 (dt, J = 4.0, 2.0 Hz, 1 H, 5'-H). ¹³ C NMR (151 MHz, CDCh) ö = 15.4 (q, 3'-Me), 24.8 (t, C-1 '), 25.6 / 27.6 (2q, Me ₂ C-8'), 29.9 (q, C-1), 31 .7 (t, C-4), 36.1 (t, C-2'), 38.7 (t, C-4'), 40.7 (t, C-9'), 41.4 (d, C-3'), 42.0 (t, C-3), 48.3 (s, C-8'), 53.5 (d, C-7'), 54.0 (s, C-3a'), 59.0 (d, C-8a'), 118.8 (d, C-5'), 143.0 (s, C-6'), 208.9 (s, C-2). GC-MS (70eV): m/z (%): 43 (44), 55 (17), 69 (26), 79 (15), 91 (98), 105 (28), 118 (25), 131 (18), 147 (12), 159 (34), 175 (100), 187 (9), 202 (46), 217 (24), 245 (3), 260 (16).

Example 3: Application of the compounds in a multifaceted dry-woody amber composition with fresh-citrusy contrast

perfume composition 3.1

Compound (2) gives the composition more performance, character and a typical signature through the dark, woody, amber-like contrast. It brings an ambery dynamic that reinforces the woody basic character of the fragrance. In addition, compound (2) harmonizes with the fresh, citrus top note and gives it more radiance. Compound (2) also makes the entire fragrance long-lasting and long-lasting.

perfume composition 3.2

Compound (1) makes the overall olfactory impression stronger and longer lasting. In addition, compound (1) gives the composition a distinctive masculine character and harmonizes excellently with the sweet and powdery facets of the perfume and highlights them.

perfume composition 3.3

Compound (3) brings interesting new facets to the fragrance composition: it makes the composition as a whole more complex, stronger, longer lasting and more modern. The fragrance smells warmer and soft-amber. The citrus notes now appear more multifaceted and clearer. In addition, compound (3) refines the composition with a fresh, peppery facet and even luxurious hints of incense. Perfume composition 3.4

The combination of compound (2) and Ambrocenide® creates a clean musk note with a warm amber undertone.

Perfume composition 3.5:

The combination of compound (1) and Ambrocenide® rounds off the harsh note of Ambrocenide® and makes the amber complex appear softer and more sensual. Perfume composition 3.6

In combination between compound (3) and Ambrocenide®, the composition appears more authentic, noble and sensual, as the combination effect creates warm, attractive pepper, incense and agarwood notes.

Claims

patent claims 1 . A compound or a mixture of compounds of formula (I) including all stereoisomers,

where X and Y = H or -OMe, and X = H if Y = -OMe, and Y = H if X = -OMe or X = Y = H. 2. Use of a compound or mixture of compounds according to claim 1 as a fragrance, in particular as an amber-like fragrance and/or for enhancing and/or modifying an amber-like and/or agarwood note of other fragrances and/or as a fixative, in particular for prolonging the adhesion of an amber-like and/or agarwood note of other fragrances. 3. Use of a compound according to claim 2, wherein compound (1)

used to convey, enhance, modify and/or fix an amber and/or agarwood note. 4. Use of a compound according to claim 2, wherein compound (2)

used to convey, enhance, modify and/or fix a woody, amber, agarwood, peppery and/or green note. 5. Use of a compound according to claim 2, wherein compound (3)

used to convey, enhance, modify and/or fix a woody, amber, agarwood, peppery and/or green note. 6. A fragrance composition comprising or consisting of a compound or mixture of compounds as defined in claim 1, in particular comprising compound (1), compound (2) and/or compound (3), and one or more further fragrance(s). 7. A fragrance composition according to claim 6, comprising or consisting of compound (1), compound (2) and/or compound (3) and at least one amber or agarwood fragrance. 8. A fragrance composition according to claim 6 or 7, wherein the compounds (1), (2) and/or (3) each make up 0.001 to 10 wt.% of the fragrance composition, preferably 0.2 to 2 wt.%. 9. Fragrance composition according to one of claims 7 or 8, wherein the amber fragrance(s) and/or agarwood fragrance(s) is/are selected from the group consisting of the stereoisomeric 2,2,5,8,8,9a-hexamethyl- octahydro-4/7-4a,9-methanoazuleno[5,6-c/][1,3]dioxole, 2,5,8,8,9a-pentamethyl- 2-propyloctahydro-4/7-4a,9-methanoazuleno[5,6-cf][1,3]dioxole, 2,5,8,8,9a-pentamethyl-2-(prop-1-en-1-yl)octahydro-4H-4a,9-methanoazuleno[5,6-d][1,3]dioxole, 2-(Methoxymethyl)-2, 5,8,8, 9a-pentamethyloctahydro-4/7-4a,9-methanoazuleno[5,6-d][1,3]dioxole, 2,4-Dimethyl-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-naphthalen-2-yl)-1,3-dioxolane, 2',2',3,7,7-Pentamethylspiro[bicyclo[4.1,0]heptane-2,5'-[1,3]dioxane], 2'-isopropyl-1,7,7-trimethylspiro[bicyclo[2.2.1]heptane- 2,4'-[1,3]dioxane], 1-(2',2',6'-trimethylcyclohexyl)hexan-3-ol, 2-methyl-5-(5',5',6'-trimethylbicyclo[2.2.1 hept-2'-yl)cyclohexanone, decahydro-2,2,6,6,7,8,8-heptame- thyl-2/7-indeno[4,5-b]furan,6,7-dihydro-1,1,2,3,3-pentamethyl-4(5/-/)-indanone, 1 a,3,3,4,6,6-hexamethyl-1 a,2,3,4,5,6,7,7a-octahydronaphtho[2,3-b]oxirene, 7.7.8.9.9-Pentamethyl-4,4a,5,6,7,8,9,9b-octahydroindeno[4,5-cf][1,3]dioxin, 7.7.8.9.9-Pentamethyl-6,6a,7,8,9,9a-hexahydro-5/7-cyclopenta[h]quinazoline, 7.7.8.9.9-pentamethyl-6,7,8,9-tetrahydro-5/7-cyclopenta[h]quinazoline, 2, 6, 6, 7,8,8-hexamethyldecahydro-2/7-indeno[4,5-b]furan, 2,2,6,6,7,8,8-heptamethylde- cahydro-2/7-indeno[4,5-b]furan, 2,2,7,7,8,9,9-heptamethyldecahydroindeno[4,3a-b]furan, 7-methoxy-1,1,5,5-tetramethyl-1,3,4,5,6,7-hexahydro-2/7-2,4a-methonaphthalene, 5,5-Dimethyl-2-propylhexahydro-2/7-2,4a-methanonaphthalene-1 (5/-/)-one, 2,2,9, 11-tetramethylspiro[5.5]undec-8-en-1-yl acetate, 3,8,8,1 1 a-tetramethyldodecahydro-5H-3,5a-epoxynapht[2,1-C]oxepin, 3a,6,6,9a-tetramethyl- 1 ,2,3a,4,6,7,8,9,9a,9b-decahydronaphtho[2,1-b]furane and 3a,6,6,9a-tetramethyldodecahydronaphtho[2,1-b]furane as well as the reaction products from the acid-catalyzed cyclization of 1-(1 ’,6’-dimethyl-4’-(4”-methylpent-3”-en-1 ”- yl)cyclohex-3’-en-1 ’-yl)ethan-1-one. 10. A method for perfuming a product comprising the steps: (i) providing a compound or mixture of compounds according to claim 1 or a fragrance composition according to any one of claims 6 to 9, and (ii) adding the compound or mixture of compounds or the fragrance composition to the product to be perfumed, preferably in a sensorially effective amount, in particular in an amount sufficient to impart, enhance and/or modify an olfactory note. 11. The method according to claim 10, wherein in step (ii) compound (1) is added to the product to be perfumed in order to impart, enhance, modify and/or fix an amber-like and/or agarwood note and/or wherein compound (2) is added to the product to be perfumed in order to impart, enhance, modify and/or fix a woody, amber-like, agarwood, peppery and/or green note and/or wherein in step (ii) compound (3) is added to the product to be perfumed in order to impart, enhance, modify and/or fix a woody, amber-like, agarwood, peppery and/or green note. 12. A perfumed product comprising a compound or mixture of compounds according to claim 1 or a fragrance composition according to any one of claims 6 to 9. 13. Perfumed product according to claim 12, wherein the product is selected from the group consisting of detergents and cleaning agents, hygiene and care products, preferably in the field of body and hair care, cosmetics and household, preferably selected from the group consisting of perfume extracts, eau de parfums, eau de toilettes, aftershave lotions, eau de colognes, pre-shave products, perfumed wet wipes, acidic, alkaline or neutral detergents, textile fresheners, ironing aids, liquid detergents, powdered detergents, laundry treatment agents, fabric softeners, laundry soaps, detergent tablets, disinfectants, surface disinfectants, air fresheners, aerosol sprays, waxes and varnishes, body care products, hand creams and lotions, foot creams and lotions, depilatory creams and lotions, aftershave creams and lotions, tanning creams and lotions, hair care products, deodorants, antiperspirants, decorative cosmetic products, candles, lamp oils, incense sticks, insecticides, repellents and propellants. 14. Perfumed product according to claim 12 or 13, wherein the total amount of the fragrance composition is in a range of 0.05 to 5 wt.%, preferably 0.5 to 2 wt.%, each based on the total weight of the product.