ABSTRACT This study examines the fate of commonly found organic natural products under exposure t... more ABSTRACT This study examines the fate of commonly found organic natural products under exposure to ozone to simulate early oxic diagenesis. The model compounds β-amyrin, lupenone and friedelin have been investigated by ozonation in the presence of water. The transformation products were identified or proposed based on their fragmentation patterns in mass spectra. The double bonds located at the isopropenyl group of lupenone and ring C of β-amyrin are the main reaction sites in the ozonation reaction. The major products identified from the ozonation of β-amyrin are β-amyrone, 12,13-epoxyoleanan-3β-ol, 11-oxo-olean-12-en-3β-ol, 12-oxo-oleanan-3β-ol. In addition, 8,14-seco-12-oxo-olean-14-en-3β-ol, 8,14-seco-12-oxo-olean-13-en-3β-ol and 8,14-seco-oleana-3,12-dione, generated from the bond cleavage between C-8 to C-14 of 12-oxo-oleanan-3β-ol and 12-oxo-oleanan-3-one, respectively, have also been detected. 22,29,30-trisnorlup-18(19)-en-3-one, 22,29,30-trisnorlupan-3-one, 22,29,30-trisnorlupana-3,19-dione, 22,29,30-trisnorlupana-3,12-dione, lupeol, lup-22(29)-en-3-on-29-ol, 22,29-epoxylupan-3-one, lupan-3-on-29-al, lupan-3-on-29-ol and 19,22-epoxylupan-3-one are the major products from the ozonation of lupenone. No transformation product was detected for friedelin, probably due to its stability to ozonation.
Environmental Science and Pollution Research, 2013
This study investigated the degradation pathway of metoprolol, a widely used β-blocker, in the oz... more This study investigated the degradation pathway of metoprolol, a widely used β-blocker, in the ozonation via the identification of generated ozonation by-products (OPs). Structure elucidation of OPs was performed using HPLC coupled with quadrupole time-of-flight high-resolution mass spectrometry. Seven OPs were identified, and four of these have not been reported elsewhere. Identified OPs of metoprolol included aromatic ring breakdown by-products; aliphatic chain degraded by-products and aromatic ring mono-, di-, and tetrahydroxylated derivatives. Based on the detected OPs, metoprolol could be degraded through aromatic ring opening reaction via reaction with ozone (O3) and degradation of aliphatic chain and aromatic ring via reaction with hydroxyl radical (•OH).
... Bera, Malaysia. Noorhazlina Abu Bakar a , Kheng Soo Tay a , Nasr Yousef MJ Omar a , M. Radzi ... more ... Bera, Malaysia. Noorhazlina Abu Bakar a , Kheng Soo Tay a , Nasr Yousef MJ Omar a , M. Radzi Bin Abas a , Corresponding Author Contact Information , E-mail The Corresponding Author and Bernd RT Simoneit b , c. a Environmental ...
ABSTRACT This study examines the fate of commonly found organic natural products under exposure t... more ABSTRACT This study examines the fate of commonly found organic natural products under exposure to ozone to simulate early oxic diagenesis. The model compounds β-amyrin, lupenone and friedelin have been investigated by ozonation in the presence of water. The transformation products were identified or proposed based on their fragmentation patterns in mass spectra. The double bonds located at the isopropenyl group of lupenone and ring C of β-amyrin are the main reaction sites in the ozonation reaction. The major products identified from the ozonation of β-amyrin are β-amyrone, 12,13-epoxyoleanan-3β-ol, 11-oxo-olean-12-en-3β-ol, 12-oxo-oleanan-3β-ol. In addition, 8,14-seco-12-oxo-olean-14-en-3β-ol, 8,14-seco-12-oxo-olean-13-en-3β-ol and 8,14-seco-oleana-3,12-dione, generated from the bond cleavage between C-8 to C-14 of 12-oxo-oleanan-3β-ol and 12-oxo-oleanan-3-one, respectively, have also been detected. 22,29,30-trisnorlup-18(19)-en-3-one, 22,29,30-trisnorlupan-3-one, 22,29,30-trisnorlupana-3,19-dione, 22,29,30-trisnorlupana-3,12-dione, lupeol, lup-22(29)-en-3-on-29-ol, 22,29-epoxylupan-3-one, lupan-3-on-29-al, lupan-3-on-29-ol and 19,22-epoxylupan-3-one are the major products from the ozonation of lupenone. No transformation product was detected for friedelin, probably due to its stability to ozonation.
Environmental Science and Pollution Research, 2013
This study investigated the degradation pathway of metoprolol, a widely used β-blocker, in the oz... more This study investigated the degradation pathway of metoprolol, a widely used β-blocker, in the ozonation via the identification of generated ozonation by-products (OPs). Structure elucidation of OPs was performed using HPLC coupled with quadrupole time-of-flight high-resolution mass spectrometry. Seven OPs were identified, and four of these have not been reported elsewhere. Identified OPs of metoprolol included aromatic ring breakdown by-products; aliphatic chain degraded by-products and aromatic ring mono-, di-, and tetrahydroxylated derivatives. Based on the detected OPs, metoprolol could be degraded through aromatic ring opening reaction via reaction with ozone (O3) and degradation of aliphatic chain and aromatic ring via reaction with hydroxyl radical (•OH).
... Bera, Malaysia. Noorhazlina Abu Bakar a , Kheng Soo Tay a , Nasr Yousef MJ Omar a , M. Radzi ... more ... Bera, Malaysia. Noorhazlina Abu Bakar a , Kheng Soo Tay a , Nasr Yousef MJ Omar a , M. Radzi Bin Abas a , Corresponding Author Contact Information , E-mail The Corresponding Author and Bernd RT Simoneit b , c. a Environmental ...
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