Compound 1 as a key intermediate of 1, 7, 9-trideoxytaxol was synthesized in ten steps from a biosynthetically available taxane, Sinenxan A. The key steps in the synthesis were deoxygenation at C-14, allylic oxidatio...Compound 1 as a key intermediate of 1, 7, 9-trideoxytaxol was synthesized in ten steps from a biosynthetically available taxane, Sinenxan A. The key steps in the synthesis were deoxygenation at C-14, allylic oxidation at C-13 and construction of the oxetane ring.展开更多
(+)-cis-(1S, 2R)-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into (-)fosfomycin by a seven-step ...(+)-cis-(1S, 2R)-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into (-)fosfomycin by a seven-step procedure. The esterification of the dihydroxyphosphonic intermediate was the key step. The title compound was obtained in good yield and its optical purity was up to the medicine quality standard of Chinese Pharmacopoeia.展开更多
1-Hydroxyl acetylation of 10-deacetylbaccatin Ⅲ was achieved by removing the neighboring bulky 2-benzoyl group and oxidizing 2-hydroxyl group to a ketone function, but attempted reductive cleavage of 1-acetoxy gave r...1-Hydroxyl acetylation of 10-deacetylbaccatin Ⅲ was achieved by removing the neighboring bulky 2-benzoyl group and oxidizing 2-hydroxyl group to a ketone function, but attempted reductive cleavage of 1-acetoxy gave rearranged products under different conditions with or without proton source.展开更多
A series of benzimidazole derivatives have been designed, synthesized and evaluated for H1 antihistamine activity. Six compounds have showed potent antihistamine H1 activity. The primary SAR analysis indicated that be...A series of benzimidazole derivatives have been designed, synthesized and evaluated for H1 antihistamine activity. Six compounds have showed potent antihistamine H1 activity. The primary SAR analysis indicated that benzyl or benzylidinyl substituted on the exo-nitrogen atom and C2 of the benzimidazole were significant. Further experiments indicated that compound 17d displayed excellent activity to reduce mast cell degranulation, moderate anti-PAF activity and decreased potency on hERG compared to astennizole. Hence compound 17d could serve as anti-allergic agent for further development.展开更多
Thirteen thiomorpholine-bearing compounds were designed and synthesized as dipeptidyl peptidase IV(DPP-IV) inhibitors, with natural and non-natural L-amino acids as the starting materials.Their structures were chara...Thirteen thiomorpholine-bearing compounds were designed and synthesized as dipeptidyl peptidase IV(DPP-IV) inhibitors, with natural and non-natural L-amino acids as the starting materials.Their structures were characterized by ~1H NMR,^(13)C NMR and HR-MS.The target compounds were screened for the DPP-IV inhibition,and the preliminary SAR result was obtained.Particularly, compounds 4c,4d and 4f with good DPP-IV inhibition in vitro were further evaluated through a mouse oral glucose tolerance test (OGTT).The preliminary result showed the potential value for further studies on those thiomorpholine-bearing compounds as DPP-IV inhibitors.展开更多
(-)-(3R, 4S)-3-Acetoxy-4-phenylazetidin-2-one ((-)-1) was the key intermediate for preparing optical C-13 side-chain moiety in partial synthesis of docetaxel and paclitaxel. It can be successfully prepared via...(-)-(3R, 4S)-3-Acetoxy-4-phenylazetidin-2-one ((-)-1) was the key intermediate for preparing optical C-13 side-chain moiety in partial synthesis of docetaxel and paclitaxel. It can be successfully prepared via enantioselective hydrolysis of racemic esters ((-4-)-1) catalyzed by bacterial lipases, but the current reaction evaluation method is tedious and inconvenient. Electronic circular dichroism (ECD) has been widely applied in the stereochemical study of chiral compounds. In this paper, a rapid ECD spectroscopic method has been proposed and established to detect the transformation directly. The absolute configurations of lipase-catalyzed hydrolysis products have also been confirmed by quantum-chemical calculation using time-dependent density functional theory (TDDFT) methodology.展开更多
基金This research work was financially supported by NNSFC.
文摘Compound 1 as a key intermediate of 1, 7, 9-trideoxytaxol was synthesized in ten steps from a biosynthetically available taxane, Sinenxan A. The key steps in the synthesis were deoxygenation at C-14, allylic oxidation at C-13 and construction of the oxetane ring.
基金supported by R & D Special Funds for National Engineering Research Center sponsored by MOST of PR China.
文摘(+)-cis-(1S, 2R)-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into (-)fosfomycin by a seven-step procedure. The esterification of the dihydroxyphosphonic intermediate was the key step. The title compound was obtained in good yield and its optical purity was up to the medicine quality standard of Chinese Pharmacopoeia.
基金The authors gratefully acknowledge financial support from the National Natural Science Foundation of China(No.39370809)National New Drug Foundation(No.92-08-N).
文摘AF-5 was synthesized through a convergent method. The key step was the Robinson annulation using a key intermediate pentyl vinyl ketone.
文摘1-Hydroxyl acetylation of 10-deacetylbaccatin Ⅲ was achieved by removing the neighboring bulky 2-benzoyl group and oxidizing 2-hydroxyl group to a ketone function, but attempted reductive cleavage of 1-acetoxy gave rearranged products under different conditions with or without proton source.
基金supported by National Major Scientific and Technological Special Project(No.2009ZX09301 -003)
文摘A series of benzimidazole derivatives have been designed, synthesized and evaluated for H1 antihistamine activity. Six compounds have showed potent antihistamine H1 activity. The primary SAR analysis indicated that benzyl or benzylidinyl substituted on the exo-nitrogen atom and C2 of the benzimidazole were significant. Further experiments indicated that compound 17d displayed excellent activity to reduce mast cell degranulation, moderate anti-PAF activity and decreased potency on hERG compared to astennizole. Hence compound 17d could serve as anti-allergic agent for further development.
基金the Fundamental Scientific Research Fund ofInstitute of Materia Medica(Li Peng 504-Basic 10 DPP IV inhibitor)for financial support on this project
文摘Thirteen thiomorpholine-bearing compounds were designed and synthesized as dipeptidyl peptidase IV(DPP-IV) inhibitors, with natural and non-natural L-amino acids as the starting materials.Their structures were characterized by ~1H NMR,^(13)C NMR and HR-MS.The target compounds were screened for the DPP-IV inhibition,and the preliminary SAR result was obtained.Particularly, compounds 4c,4d and 4f with good DPP-IV inhibition in vitro were further evaluated through a mouse oral glucose tolerance test (OGTT).The preliminary result showed the potential value for further studies on those thiomorpholine-bearing compounds as DPP-IV inhibitors.
文摘(-)-(3R, 4S)-3-Acetoxy-4-phenylazetidin-2-one ((-)-1) was the key intermediate for preparing optical C-13 side-chain moiety in partial synthesis of docetaxel and paclitaxel. It can be successfully prepared via enantioselective hydrolysis of racemic esters ((-4-)-1) catalyzed by bacterial lipases, but the current reaction evaluation method is tedious and inconvenient. Electronic circular dichroism (ECD) has been widely applied in the stereochemical study of chiral compounds. In this paper, a rapid ECD spectroscopic method has been proposed and established to detect the transformation directly. The absolute configurations of lipase-catalyzed hydrolysis products have also been confirmed by quantum-chemical calculation using time-dependent density functional theory (TDDFT) methodology.