DD138663B1 - PROCESS FOR EPIMERIZING GIBBERELLIN-7-ALDEHYDE - Google Patents

Description

A method for the spimerization of Gib bejre llin-7-aldehydes

The invention relates to a process for the epimerization of gibberellin-7-aldehydes. Gibberellin-7-aldehydes are gibberellin derivatives which have an aldehyde group in position 6 of the ent- gibberellan skeleton. In this case, the aldehyde group can be in the natural 6β or in the epimeric position (the ent- gibberellan nomenclature is generally used).

In gibberellin-7-aldehydes, the ent- gibberellan skeleton is intact or slightly modified (eg seco-, horno-, nor- or dinor-ent-gibberellin, optionally epimerized and containing multiple bonds) and optionally substituted in various ways. As labeled gibberellin-7-aldehydes are defined those compounds which are tritiated or deuterated.

Field of application of the invention

Gibberellins have great biological significance as phytohormones of multiple action. It is known that structural modification of such naturally occurring gibberellins leads to compounds with altered biological activity.

Furthermore, gibberellins are used in the form of their labeled representatives, e.g. for biotechnological procedures, for the study of biosynthesis, metabolism, transport, distribution, mode of action and structural analysis of these phytohormones and their partial3 synthetic structural analogues

as a basis for the synthesis of new drugs.

Characteristic of the known technical solutions

The preparation of some gibberellin-7-aldehydes has already been described. Thus, gibberellin-7-aldehydes are known which have an aldehyde group in the natural 6β-position of the ent- gibberellan skeleton / "" M. LISCHWSKI and G. ADAM, DDR patent 112 753; M. LISCHEWSKI and G. ADAM, Tetrahedron Letters 2835 (1974); M. LISCHSWSKI and G. ADAM, GDR Patent 120,875; M. LISCHEWSKI and G. ADAM, Tetrahedron Letters 2569 (1975); M. LISCHEWSKI and G. ADAM, Z. Chem. 1_6, 486 (1976); JR HANSON and J. HAWKER, J. Chem. Soc. Chen. Comm. 1971 »208 and Phy to chemistry JM2, 1073 (1973); BE CROSS, K. NORTON and JC STEWART, J. Chem. Soc. (C) 1968, 1054; BE CROSS and IL GATPIELD, ibid. 1971 , 1539.7.

In contrast, no gibberellin-7-aldehydes have been synthesized which have an aldehyde group in the epimeric 6oc position.

The preparation of some labeled gibberellin 7-aldehydes with aldehyde group at 6β position has also been reported. Thus, the production of / Jo and £ ζ> was - нУ gibberellin Ap-aldehyde and -Gibberellin-A .. - aldehyde is £ ~ J. R. BEARDER, J. Mac MILLAN and BO PHINNEY, Phytochemistry 1_2, 2173, 2615 (1973); JH GRAEBE, P. HEDDEN and J. Mac MILLAN, J. former Soc. Chem. Comm. 1975 , 161, P.HEDDEN, J. Mac MILLAN and BO PHILIIEY, J. Chem. Soc., Perkin I 1974 , 587_7. However, because of the harsh conditions (long reaction times, high base excess, elevated temperatures), this method is applicable only to these base stable gibberellin 7-aldehydes and provides only low yields.

Furthermore, the synthesis of /7- ^ ^H.17-14 C / gibberellin A ₁₂ -aldehyde is known / ^ B. DOCKERILL, R. EVANS and JR HANSON, J. ohem. Soc. Chem. Comm. 1977 , 919J7. Such in position

tritiated gibberellin-7-aldehydes have the disadvantage that in the biosynthetic or chemical conversion of the 7-aldehyde function to the carboxyl group, the tritium is removed.

Object of the invention

The aim of the invention is to make gibberellin-7-aldehydes with aldehyde group located in the 6oC position accessible for the first time and thereby to make available a new group of biological active compounds. The process for their preparation should be generally applicable and at the same time suitable for the labeling of gibberellin-7-aldehydes in good yields.

Explanation of the essence of the invention

The object of the invention is to epimerize known gibberellin-7-aldehydes under mild conditions, whereby the method should also be suitable for the simultaneous tritiation or deuteration on a C-H bond which is present in all gibberellin-derived from natural gibberellins and their derivatives aldehydes are present unsubstituted and have not been observed in the biochemical changes so far to ensure a wide range of applications of the method.

According to the invention, a gibberellin 7-aldehyde having a 6o-position or 6-position aldehyde group is enclated with a base and adding compounds having hydrogen, deuterium or tritium donor properties to a mixture of epimers consisting of a gibberellin 7-aldehyde with the aldehyde group in the position of the boron and a gibberellin-7-aldehyde with the aldehyde group in the position 6ß, wherein when using compounds with deuterium or tritium donor properties, both epimers obtained are marked on the carbon atom 6.

The alo starting materials used Gibbsrellin-7-aldehydes are prepared by known methods on chemical / ~ M. LISCHEY / SKI and G. ADAM, DDR patent 112 753, C 07 d, 5/06; DDR patent 120 875, C 07 D, 307/77 {M. LISCHEV / SKI and

G. ADAM, Tetrahedron Letters 1974 , 2835; ibid. 1975 , 2569; ibid. 1975 , 3691; Z. Chem. VS, 486 (1976) J7 or microbial routes / ~ JR BEARDER, J. MacMILLAN and BO PHINHEY, Phytochemistry 12, 2173 (1973); JR IiAITSON and J. HAWKER, J. Chem. Soc., Chem. Comm. 1971, 203 and Phytochemistry 12, 1073 (1973) _7.

The process of the invention is used in the absence of air, e.g. under an argon or nitrogen atmosphere, in an organic solvent, preferably in abs. Tetrahydrofuran or abs. Dioxane.

The bases used in the process according to the invention are preferably strong but less nucleophilic bases. Particularly advantageous in this case are alkali metal _s, preferably those having room-filling organic radicals, for example lithium diisopropyl = amide or lithium 2,2,6,6-tetramethylpiperidide, or hydrides, in particular potassium hydride. Through the use of this strong, but not very nucleophilic bases Cn gibberellin-7-aldehyde with 19- 10 f lactone ring are first enolizable. A particular advantage of the process according to the invention is that the base is only required in an equivalent amount or in slight excess (for example 1.1 equivalents) for enolate formation. This applies to gibberellin 7-aldehydes without acidic hydrogen atoms (eg gibberellin Aq-7-aldehyde). When gibberellin-7-aldehydes are used with acidic hydrogen atoms (for example gibberellin-7-aldehydes containing hydroxyl or carboxyl groups), it is expedient to substitute these hydrogen atoms. As a protective group for hydroxyl groups, for example, the trimethylsilyl group, the tert. Butyldimethylsilylgruppe or tetrahydropyranyl group used. In contrast, carboxyl groups are esterified or neutralized by excess base. The enolization of gibberellin-7-aldychydes in the presence of acidic hydrogen atoms is also possible. In this case, however, more equivalents of base are required so that enolate formation can take place.

As compounds with hydrogen, deuterium or tritium

Donator properties (hereinafter called hydrogen, deuterium or tritium donors) are the most diverse compounds with exchangeable hydrogen, deuterium or

Tritium suitable, for example H ₀ O, ² H ₀ O, H ₀ O, H-OR,

2 3 H-OR, H-OR, where R is a substituted or unsubstituted

Alkyl, aryl or acyl group stands, but also, organic or inorganic acids. When acids are used, the resulting gibberellin 7-aldehydes are not exposed to alkaline and nucleophilic conditions, which is particularly important for the preparation of base unstable gibberellin 7-aldehydes.

Regardless of whether one starts with the labeling of a gibberellin 7-aldehyde with in 6ß-position aldehyde group or of such with 6c <position aldehyde group, one always obtains both labeled gibberellin 7-aldehydes in 6ß position aldehyde group as well as labeled gibberellin 7-aldehydes with aldehyde group at 6o £ position ·

Both during enolate formation and when reacted with hydrogen, deuterium or tritium donors, the temperature can be varied within a wide range. Conveniently, one works between -78 ⁰ C and room temperature.

The workup of the reaction products by the usual methods, for example by column chromatography using organic solvents. It is noteworthy that the two resulting epimers in the process according to the invention are characterized by easy chromatographic separability.

The method of the invention is generally applicable to gibberellin-7-aldehydes, wherein base instable structural features are not altered. For the first time, unlabelled or labeled gibberellin-7-aldehydes with aldehyde groups in the 6-position can be obtained by this process. Due to the mild conditions of the reaction, the invention

appropriate procedures for the epimerization and labeling of C ^ Q-gibberellin-7-aldehydes with 19- ^ 10 lactone ring suitable. For example, 6-H / or 6-H / gibberellin A. 7-aldehyde, gibberellin A-15 aldehyde, gibberellin A. 15-aldehyde, gibberellin Ac-7 aldehyde, gibberellin-AW-aldehyde, gibberellin-Ag-7-aldehyde and gibberellin-Ag-7-aldehyde, which previously could not be prepared by other means.

In addition, labeled gibberellin-7-aldehydes, e.g. / * 6- ЬіЛ-gibberellin A ^ -T aldehyde / synthesized in higher yield than previously described.

Also, the preparation of double-labeled gibberellin-7-aldehydes i &'t possible by the method according to the invention. For example, gaining in this way / Ϊ7- C, 6- 37-gibberellin A ₃ ~ -7-aldehyde and Zi7- ¹⁴ C, 6- ³ H7-6-Epigibberellin-A ₃ -7-aldehyde from / i7 ^U q / -Gibberellin-A ₃ -7-aldehyde, Zi- ³ H, H7 6- ^{3-gibberellin} A _I --7-aldehyde and / i-3 H, 6 H ³ / -6-Epigibberellin-Aj.-7 aldehyde from / Ί- H7 gibberellin-A, - 7-aldehyde and ZB ³ H, 15-H ³ / -Gibberellin-A ₃ -7-aldehyde and Z ~ 6- ³ H, 15- ^ ³ II7 -Epigib berellin-A ₃ -7-aldehyde from / i5 ³ H7 gibberellin A ₃ -7-aldehyde.

The obtained by the process according to the invention gibberellin 7-aldehydes with befindliches in 6ot-position aldehyde group show a geganüber the starting materials modified biological activity.

Characteristic of the labeled gibberellin-7-aldehydes prepared according to the method of the invention is that the label is stable and achievable with a high specific radioactivity. Since the label on the one hand is extremely easy to detect or localize and on the other hand is located at a position where biochemical changes have not been observed, these compounds are for example suitable for biosynthesis studies or Metabolismusuntersuchungen. In addition, the labeled gibberellin-7-aldehydes prepared according to the invention serve as starting materials for the production of labeled

natural gibberellins and their derivatives.

The following examples illustrate the invention, wherein the specific conditions specified therein do not limit the invention and the reaction conditions are also applicable to the preparation of other compounds.

Exemplary embodiments

To 330.4 mg (1 mmol) of gibberellin Ao-7-aldehyde (Ia) dissolved in 15 ml abs. Pyridine, are added 2 ml of hexamethyldisilazane and 2 ml of trimethylchlorosilane. It is allowed to stand for 3 hours at room temperature and concentrated i.Vak. on. After addition of sat. NaHCCU solution is exhaustively shaken with ether. The combined ether phases are washed with anhydrous MgSO4. dried and i.vak. concentrated. The residue is over РдО.д overnight i.Vak. ditched. Subsequently, the silylated gibberellin-A-э-7-aldehyde is dissolved under argon in 8 ml of oxygen-free and abs. THF and added at room temperature 44 mg (1.1 mmol) of potassium hydride. After stirring for one hour at room temperature, 1 ml of glacial acetic acid and 2 ml of water are added. The solution is then allowed to stand for removal of the protecting groups on Hacht, then concentrated and after addition of sat. NaHCOo solution shaken several times with ethyl acetate. Drying of the organic phases with Na ₂ SO. and constricting i.Vak. gives a residue, which is chromatographed on 20 g KieseLgel (V / oelm). Elution with chloroform (fractions 1-35) »chloroform / ethyl acetate 9: 1 v / v (fractions 36-60), chloroform / ethyl acetate 8: 2 v / v (fractions 61-90) and chloroform / ethyl acetate 7: 3 v / v (fractions 91-150) yields 68-89 96 mg starting aldehyde Ia when pooling fractions. From the fractions 94-141 isolated 143 mg = 61 % d. Th. Ö-epigibberellin A ^^ - aldehyde (Ib) (yield calculation based on reacted aldehyde Ia): mp 185-187 ⁰ C (from acetone / η-hexane); CoLj ^ 0 ° (c = 0.35 - ethanol); LIS: m / e 330 (M ⁺ or M ~); IR (CH 2 Cl 2): P _Y 3600 (OH), 2730 and 1725 (aldehyde),

1775 (f-Ьасton-СО) and 1665 cm " ¹ (= CH ₂ );

100 MHz ¹ H-NMR: b 1 ^-ton " ^D 6 1.19 (s, 18-H ₃ ), 2.75 (dd, J = 10 Hz and J x = 2.5 Hz, 6-H), 2.97 (d, J = 10 Hz, 5-H),

4.32 (m, 3-H),

4.89 and 5.21 (m, 17-Hz),

5.84 (dd, J = 9 Hz and J ^f = 2.5 Hz, 2-H), 6.28 (dd, J = 9 Hz and J x = 2 Hz, 1-H) and 9.80 ppm (d, J = 2.5 Hz, 7-H).

Analogously, 1 g of gibberellin 7-aldehyde with 6β-position aldehyde group and 1.1 mmol of potassium hydride, the following gibberellin-7-aldehydes are shown with located in 6a-position aldehyde group:

6-epigibbereaiin-A ₁ -7-aldehyde (Hb):

Yield: 153 mg '= 64 % d. Th. (93 mg Ha recovered); Elution with chloroforra / ethyl acetate 7: 3 v / v; Mp 182-186 ⁰ C (from acetone / n-hexane). MS: m / e 332 (M ⁺ );

IR (uujol): >> _ 3410 (br, OH), 1755 (g-lactone-CO) and

л Іисіл, "

1720 cm "" '(aldehyde)

6-epigibberellin A ₄ -7-aldehyde (HIb):

Yield: 152 mg = 66 % d. Th. (86 mg of IHa recovered); Elution with chloroform; amorphous; MS: m / e 316 (M ⁺ );

IR (CHClO): μ> 3610 (OH), 2725, 2820 and 1725 (aldehyde) and 1775 cm ^-1 (α-lactone CO).

6-epigibberellin A ₅ -7-aldehyde (IVb):

Yield: 152 mg = 70 % d. Th. (97 mg IVa recovered); Elution with chloroform;

M.p. 195-197 ⁰ C (from chloroform / n-hexane); MS: m / e 314 (M ⁺ );

IR (Nujol) tf _m __ 3400 (br, OH), 1755 (/ -lactone-CO) and

лал. I

" ¹

1720 cm ^-1 (aldehyde).

6-epigibberellin-Ag-7-aldehyde (Vb):

Yield: 150 mg = 60% d. Th. (93 mg Va recovered); Elution with chloroform / ethyl acetate 2: 8 v / v; amorphous; MS: m / e 348 (M ⁺ ); IR (Nujol): _mav 3400 (br, OH), 1750 (f-lactone-CO) and

л Шал «

" ¹

1720 cm ^-1 (aldehyde).

6-epigibberellin A _g -7-aldehyde (VIb):

30 mg (0.1 mmol) of Via and 9 mg of potassium hydride are used.

Silylation is not necessary here.

Yield: 14.2 mg = 69 % VIb (9 »7 mg via); Elution with n-hexane / chloroform 4: 6 v / v; amorphous; FiS: m / e 30 O ₁ (M ⁺ );

IR (CH 2 Cl 2): [> _v 2725 and 1725 (aldehyde),

J I шал

1775 cm ^-1 "(f-lactone-CO).

Example_2

330.4 mg (1 mHcl) gibberellin Ao-7-aldehyde (Ia) are silylated analogously to Example 1. Thereafter, a solution of 0 (3), 0 (13) -bis-trimethylsilyl-gibberellin-A ^ -7-aldehyde in 5 ml abs. THP under argon at -78 ⁰ C dropwise with a lithium diiso = propylamidlösung (prepared from 2 ml of abs. THP, 111 mg Мізорго-pylamin and 70 mg butyl lithium).

One lets 10 Ыіп. at -78 ⁰ C, 10 min. At ^{0 0} C and 30 min at +20 ⁰ C and then 2 ml V / asser and 1 ml of glacial acetic acid. After standing for 12 hours, the mixture is worked up as in Example 1 and the crude product is chromatographed. Yield: 104 mg = 50 % of theory . Th. Δ-epigibberellin A ^^ aldehyde (Ib) (122 mg Ia recovered); Elution with chloroform / ethyl acetate 7: 3 v / v; physical and spectroscopic data see example 1 ·

To 330 mg (1 mKol) gibberellin A ₃ -7-aldehyde (Ia), which has been silylated analogously to Example 1, under argon

at -78 ° C 5 ml abs. THP and a lithium 2,2,6,6-tetra = methylpiperididlösung (prepared from 2 ml of abs. THP, 160 rag 2,2,6,6-tetramethylpiperidine and 70.4 mg of butyllithium) was added dropwise, lan leaves 10 Min. At - 78 ⁰ C, 10 min. At 0 ° C and 30 min. At +20 ⁰ C and are 1 ml of methanol and 1 ml of glacial acetic acid. After standing for 12 hours, the mixture is worked up as in Example 1 and the residue is chromatographed.

Yield: 99 mg = 47 % d. Th. 6-epigibberellin A, 7-aldehyde (Ib) (120 mg Ia recovered); Elution with chloroform / ethyl acetate 7: 3 v / v; physical and spectroscopic data see example 1.

Bei§ £ iel_4

Analogously to Example 1, gibberellin-7-aldehydes having an aldehyde group in the 6-position are prepared from 1 mmol of gibberellin-7-aldehyde with the aldehyde group in the ε position and 1.1 mmol of potassium hydride:

GibLerellin Ao-7-aldehyde (Ia):

Yield: 99 mg * 54 % d. Th. (146 mg Ib recovered); Elution with chloroform / ethyl acetate 8: 2 v / v; Mp 172-175 ⁰ C (from acetone / n-hexane) / ßoj ¹ ^ + 118.8 ° (c = 0.61 - ethanol) MS: m / e 330 (M ⁺ and M, respectively. ");

IR (CHCl ₃ ): ^ _max 3610 (OH), 2725, 2820 and 1725 (aldehyde),

"* ¹ (-CH = CH-);

1.14 (s, 18-H ₃ ), 2.79 (ad, J = 10.5 Hz and J ¹ = 2.5 Hz, 6-H), 3.29 (d, J = 10.5 Hz , 5-H), 4.06 (d, J = 3.5 Hz, 3-H), 4.93 and 5.24 (m, 17-H ₂ ),

5.90 (dd, J = 9.5 Hz and J ¹ = 3.5 Hz, 2-H), 6.39 (d, J = 9.5 Hz, 1-H) and 9.84 ppm (i.e. , J = 2.5 Hz, 7-H),

1775 (f-lactone-CO) and 1635 cm 100 MHz - ¹ H-NMR: S ^ § ^ΐοη " ^Β 6

Gibberellin A.j-7-aldehya (На):

Yield: 90 mg = 52 % d. Th. (158 rag-Hb recovered); Elution with chloroform / ethyl acetate 8: 2 v / v; amorpii;

MS: m / e 332 (M ⁺ or M ");

IR (CH 2 Cl 2): i> __ 3610 (OH), 2725, 2820 and 1725 (aldehyde) and 1770 cm (/ lactone-CO).

Gibberellin Ac-7-aldehyde (IVa):

Yield: 94 mg 59 % d. Th. (155 mg IVb recovered); Elution with n-hexane / chloroform 1: 9 v / vj mp 152-153 ⁰ C (from ether);.

KS: m / e 314 (M ⁺ );

IR (CHCl3): v? _max 3605 (OH) ₉ 2725 and 1725 (aldehyde), and

1775 cm "* (jf-lactone CO).

Gibberellin A ₈ -7-aldehyde (Va).

Yield: 95 mg = 49 % d. Th. (154 mg Vb recovered); Eluion with chloroform / ethyl acetate 4: 6 v / v; amorpii;

MS: m / e 348 (M ⁺ );

IR (Kujol): v? _max 3400 (br, OH), 1750 (f-lactone-CO) and

1720 cm ^-1 (aldehyde).

Gibberellin A ₉ -7 aldehyde (VIa):

Only 30 mg (0.1 mmol) of 6-epigibberellin-Ag-7-aldehyde are used. Silylation is not necessary here.

Yield: 9.3 mg = 62 % VIa (15 mg VIb recovered); Elution with η-hexane / chloroform 1: 1 v / v; amorphous;

MS: m / e 300 (M ⁺ ).

Beisp_iel_ £

To 330.4 mg (1 mmol) gibberellin Ao-7-aldehyde (Ia), which has been silylated analogously to Example 1, are added under argon 8 ml of abs. THF and 44 mg (1.1 mmol) of potassium hydride. After stirring for one hour, 0.1 ml% 2 ° (5.55 mmol) is added to the enolate at room temperature (specific activity 3 mCi /

mmol). The mixture is stirred for a further 3 min and then mixed with 1 ml of glacial acetic acid. Multiple Concentration i. Vak. and multiple additions of methanol allow the removal of labile tritium. To cleave the protective groups are added to the residue 8 ml of THF, 2 ml of H ^ O and 1 ml of glacial acetic acid and allowed to stand overnight. After concentration i. Vak. is ges. NaECCU solution added and shaken a few times with ethyl acetate. Dry the organic phase with Na ₂ SCL and concentrate i. Vak. provides a residue which is chromatographed analogously to Example 1. When eluted with chloroform / Sssigsäureäthylaster 8: 2 v / v 99 mg = 30% d. Th. / & -% / - gibberellin A ₃ -7-aldehyde (Ic) having a specific radioactivity of 1.37 mCi / ml. Subsequent elution with ethyl chloroform / acetic acid 7: 3 v / v yields 145 mg = 44 % of theory / B-> H7-6-epigibberellin Ao-7-aldehyde (Id) with a specific radioactivity of 1.47 mCi / mmol. The physical and spectroscopic data of these compounds can be found in Examples 1 and 4.

Analogously, from 1 mmol gibberellin 7-aldehyde with 6β-position aldehyde group, 1.1 mmol potassium hydride and 0.1 ml H-, O (specific radioactivity 3 mCi / mmol) following / B- ³ H / -gibberellin 7-aldehydes with бсі-Ctellüng located aldehyde group and / b- gibberellin-7-aldehydes prepared with 6ß-position aldehyde group. (The physical and spectroscopic data of the compounds shown are given in Examples 1 and 4):

/ B- ³ H7-Gibberellin A ₁ -7-aldehyde (lic) and / £ - ³ H / -6-epigibberellin A ₁ -7-aldehyde (Hd):

Elution with chloroform / acetic acid ethyl ester 8: 2 v / v; Yield: 93 mg 5 28% of theory lic (specific radioactivity: 1.32 mCi / mlvol); Elution with chloroform / ethyl acetate 7O v / v; Yield: 150 mg = 45 % of theory lld (specific radioactivity: 1.48 mCi / mmol).

ZS ~ ³ H / -Gibberellin-A ₄ -7-aldehyde (IIIc) and / S- ³ ± statZ-6-Ep g ± bbea Ellin-A ₄ -7-aldeiiyd (HID)?:

Elution with n-hexane / chloroform 2: 8 v / v; Yield: 91 »5 mg = 29 % d. Th. IHc (specific radioactivity: 1.35 mCi / ml); amorphous; MS: m / e 316 (M ⁺ );

IR (CHCl): _QV 3610 (OH), 2725 and 1725 (aldehyde) and

j Шал

1775. cm ^-1 (/ -lactone-CO).

Elution with chloroform;

Yield: 149 mg й 47 % of theory . Th. IHd (specific radioactivity:

1.49 mCi / mmol).

^ - ³ H / -Gibberellin-Ae-7-aldehyde (IVc), and ³ (IVd):

Elution with n-IIexane / chlorofoi'in 1: 9 v / v; Yield: 101 mg = 32 % of theory IVc (specific radioactivity: 1.39 mCi / mKol); Elution with chloroform;

Yield: 153 mg = 49 % of theory IVd (specific radioactivity:

/ £ - ³ H7-gibberellin-Ac, -7-aldehyde (Vc) and

/ "6- ^J> H / -6-epigibberellin A ₈ -7-aldehyde (Vd):

Elution with chloroform / ethyl acetate 4: 6 v / v; Yield: 100 mg = 29 % d. Th. Vc (specific radioactivity: 1.10 mCi / ml'tol);

Elution with chloroform / ethyl acetate 2: 8 v / v; Yield: 147 mg 42 % of theory Vd. (specific radioactivity: 1.21 mCi / mmol).

/ 6- ³ H / -gibberellin A ₉ -7-aldehyde (YIc) and / 6% 7-6-epigibberellin A ₉ -7-aldehyde (VId):

30 ms (0.1 mmol) of VIa and 9 mg of potassium hydride are used. Silylation is not necessary here.

Elution with n-hexane / chloroform 1: 1 v / v; Yield: 9 »9 mg = 33 %

d. Tb. VIc (specific bath activity: 1.42 mCi / mmol); Elution with n-hexane / chloroform 4: 6 v / v; Yield; 13.8 mg = 46 %

d. Th. VId (specific Eadioaktivität: 1.5 mCi / mmol).

/ B - ^ - gibberellin A ^^ - aldehyde (VIII) and / 6% 7-6-spigibberellin A ₁₂ -7-aldehyde (IX)

To a solution of 3.16 mg (0.01 mmol) gibberellin A, ^ -? - aldehyde (VII) in 0.5 ml abs. THP are added at room temperature under argon 1 mg of potassium hydride. After stirring for one hour at tree temperature, 0.1 ml HpO (specific Eadioaktivität: 3 mGi / mmol) is added and after 3 min., Are added 0.5 ml of glacial acetic acid. After that, i. Vak. concentrated and to remove the exchangeable tritium of Bückstand in Essigsäureäthylestes? dissolved and repeatedly with 2 ^ aq. Shaken out HCl. After drying with Na ₂ SO ₄ and concentration i. Vak. obtained by thin-layer chromatographic separation on silica gel (Merck)

1.27 mg = 40 % d. Th. / B- ^ HZ-Gibberellin-A ^ -T-Aiaehyde (VIII):

Mp 160-162 ⁰ C (from Acetcn / n-hexane). MS: m / e 316 (M ⁺ );

IE (GHCl _3): \> _max 2730 (aldehyde) and 1710 cm ^"1 (br, C = O) and 1.1 mg = 35% of theory. ^.

(IX): amorphous;

MS: m / e 316 (M ⁺ )

IB (CHClO: _mav 2730 (aldehyde) and 1705 cm ^-1) (br, C = O).

Analogously, from 1 mmol of gibberellin 7-aldehyde with aldehyde group in the 6oi position 1.1 mmol of potassium hydride and 0.1 ml% ₂ 0 (specific Eadioaktivität: 3 mCi / mmol) following / 5- ^ JH / gibberel lin- 7-aldehydes with in bb-position aldehyde group and

/ 6- ³ H / "gibberellin-7-aldehydes with 6β-position aldehyde group prepared (The physical and spectroscopic data of the compounds shown are given in Examples 1 and 4):

/ S- ³ H7-gibberellin A ₃ -7-aldehyde (Ic) and / 6- ³ H / -6-epigibberellin Ao-7-aldehyde (Id):

Elution with chloroform / ethyl acetate 8: 2 v / v; Yield: 103 mg = 31 % Ic (specific »radioactivity 1.5 mCi / mmol);

Elution with chloroform / ethyl acetate 7: 3 v / v; Yield: 148.3 mg = 45 % of theory Id (specific radioactivity: 1.38 xnCi / mLol).

l6 -} L7 & lbberellin-A ^ -7-alaehyd (lic) and / 6- ³ H / _{-6-Epigibberellin-A1} -7-aldehyde Я

Elution with chloroform / ethyl acetate 8: 2 v / v; Yield: 86.5 mg = 26 % of theory lic (specific radioactivity: 1.43 mCi / mLol);

Elution with chloroform / ethyl acetate 7: 3 v / v; Yield 163 mg = 49 % d.Th.Hd (specific radioactivity: 1.33 mCi / mmol).

/ 6- ³ H7-gibberellin A ₄ -7-aldehyde (HIc) and / 6- ³ bi7-6-epigibberellin A ₄ -7-aldehyde (HId):

Elution with n-hexane / chloroform 2: 8 v / v; Yield: 82 mg = 26 % of theory IHc (specific radioactivity: 1.5 mCi / mmol); Elution with chloroform;

Yield: 1 b1 mg = 51 % of theory IHd (specific radioactivity: 1.31 mCi / mLol).

/ 6- ³ H / -gibberellin A ₅ -7-aldehyde Шs) and / 6- ³ H / '- 6-epigibberi-ti ^ 1 ^^ T ^ a (IVdT:

Elution with n-hexane / chloroform 1: 9 v / v; Yield: 94 mg = d. Th. IVc (specific radioactivity: 1.5 mCi / mf.Iol);

Elution with chloroform;

Yield; 157 mg * 50% of theory IVd (specific radioactivity:

1.36 mCi / mmol).

/ 6- ³ H / gibberel- lin-A ₉ -7- aldehyde (VIc) and / 6- ³ H / -6-epigibberellin A _g -7-aldehyde (VId):

30 mg (0.1 mmol) of VIb and 9 mg of potassium hydride are used.

Silylation is not necessary here.

Elution with n-hexane / chloroform 1: 1 v / v; Yield: 9.6 mg, 32 % of theory VIc (specific radioactivity: 1.5 mCi / mblol); Elution with n-hexane / chloroform 4: 6 v / v; Yield: 15.9 mg = 53 = d.Th. VId (specific radioactivity:

1.40 mCi / mlvol).

Analogously to Example 5 is prepared from 330.4 mg (1 mmol) of gibberellin A ^ - 7-aldehyde (Ia) and 44 mg (1.1 mmol) of potassium hydride, the enolate, which with 0.1 ml of ² H ₂ O (5 , 55 mLIol; 99, no purity) is reacted. Analogous work-up and chromatography afforded / '6- ² H / -gibberellin A ₃ -7-aldehyde (X): Yield: 102.5 mg = 31 lbs. Mp 172-174 ⁰ C (from acetone / n-hexane). MS: m / e 331 (M ⁺ or M ");

in the H-liMR spectrum the protons (5-H) and (7-H) appear as singlets; the (6- ² H) is logically not visible; and / 6- ² H_7-6-epigibberellin A ₃ -7-aldehyde (XI): Yield: 142.3 mg = 43 % of theory; Mp 184-187 ⁰ C (from acetone / n-hexane). MS: m / e 331 (M ⁺ or M ") j

in the H-KtJR spectrum, the protons (5-H) and (7-H) also appear as singlets; that is missing (6- ² H).

Beisgiel_7

Analogously to Example 5, from 3.3 mg (0.01 mmol) / i7 ¹ ^ C / -Gibberellin-A ^ -7-aldehyde (specific radioactivity:. 0.23 mCi / mmol)

and 4 mg of potassium hydride, the enolate is prepared, which is then tritiated with 0.1 ml of ³ H ₂ O (specific radioactivity: 3 mCi / ml). The analog workup and thin layer chromatography provide

/ ¹⁴ C i7, 6- ³ H7 gibberellin A ₃ -7-aldehyde (. specific radioactivity ¹⁴ C: 0.23 mCi / ml.'Iol, specific radioactivity ^3H. 1.39 mCi / mmol) and . / ¹⁴ C i7, 6- ³ H7-6-Epigibberellin ~ A ₃ -7-aldehyde (specific activity radio · 4 x 0.20 mCi / mlaol, specific radioactivity ³ H;?.. 1.44 mCi / mKol ).

Claims (4)

-1t- Inventions commence A process for the epimerization of gibberellin-7-aldehydes, characterized in that a jpibberellin-7-alde'hyd enolates with a base or 6β-position aldehyde group with a base and by addition of hydrogen, deuterium or tritium donors to a Spimerengemisch consisting of a gibberellin-7-aldehyde with бое-position aldehyde group and a gibberellin-7-aldehyde with befindliches in 6ß Stellüng aldehyde group is reacted, wherein when using deuterium or tritium donors both epimers obtained at the carbon atom б are marked. 2. Method according to item 1, characterized in that the reaction is carried out in the absence of air, e.g. under argon or. Nitrogen atmosphere, is carried out in an organic solvent. 3. The method according to item 1 and 2, characterized in that as bases preferably Kaliunihydrid or alkali amides, in particular those with space-filling organic best, e.g. Lithium diisopropylamide or lithium 2,2,6,6-tetramethylpiperidid be used. 4. Process according to items 1 to 3 », characterized in that acidic hydrogen atoms in the starting compounds are substituted by protective groups before enolization. 5 Process according to items 1 to 4, characterized in that double-labeled gibberellin-7-aldehydes are prepared 14 2 in which, for example, a C- and / or H- or ^ H-gibberellin-7-aldehyde is converted to the additionally position-tritiated or deuterated gibberellin-7-aldehyde. For this JL pages formulas