Isolation and identification of the liver microsomal cytochrome P 450 isoen zymes responsible for the formation of diazepam main metabolites nordiazepam and temazepam in rats were studied. The effects of P 450 ind...Isolation and identification of the liver microsomal cytochrome P 450 isoen zymes responsible for the formation of diazepam main metabolites nordiazepam and temazepam in rats were studied. The effects of P 450 inducers and inhibitors on the protein contents in SDS poly acrylamide gel electrophoresis and thin layer chromatography to the corresponding diazepam me tabolizing activities of rat liver microsomes were observed. The P 450 contents were dramatically re duced by ip diazepam, cimetidine or propranolol. Diazepam and propranolol inhibited temazepam formation, high dose of propranolol also inhibited nordiazepam formation. Phenobarbital increased the P 450 contents and induced the production of both nordiazepam and temazepam. It also induced proteins with molecular weight (m) of 51 and 59 kDa in SDS PAGE and those with m ranging from 45 to 55 kDa and from 55 to 65 kDa in TLC. Propranolol inhibited both fractions, especially that of m 55~65 kDa, whereas diazepam tended to inhibit the fraction of 45~55 kDa. The protein of m 51 kDa could be mainly involved in diazepam C3 hydroxylation, whereas those of m 59 kDa could be responsible for the N demethylation of diazepam in rats.展开更多
Carboxylate as a promising and valuable directing group has attracted a great deal of attention.However,employing it as a traceless direction group has rarely been reported.We developed the ruthenium-catalyzed amidati...Carboxylate as a promising and valuable directing group has attracted a great deal of attention.However,employing it as a traceless direction group has rarely been reported.We developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C–H functionalization followed by decarboxylation to afford the corresponding metasubstituted N-aryl benzamides,in which the carboxylate serves as a unique,removable directing group.Notably,this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides,which are much more difficult to prepare than ortho-substituted analogues.展开更多
文摘Isolation and identification of the liver microsomal cytochrome P 450 isoen zymes responsible for the formation of diazepam main metabolites nordiazepam and temazepam in rats were studied. The effects of P 450 inducers and inhibitors on the protein contents in SDS poly acrylamide gel electrophoresis and thin layer chromatography to the corresponding diazepam me tabolizing activities of rat liver microsomes were observed. The P 450 contents were dramatically re duced by ip diazepam, cimetidine or propranolol. Diazepam and propranolol inhibited temazepam formation, high dose of propranolol also inhibited nordiazepam formation. Phenobarbital increased the P 450 contents and induced the production of both nordiazepam and temazepam. It also induced proteins with molecular weight (m) of 51 and 59 kDa in SDS PAGE and those with m ranging from 45 to 55 kDa and from 55 to 65 kDa in TLC. Propranolol inhibited both fractions, especially that of m 55~65 kDa, whereas diazepam tended to inhibit the fraction of 45~55 kDa. The protein of m 51 kDa could be mainly involved in diazepam C3 hydroxylation, whereas those of m 59 kDa could be responsible for the N demethylation of diazepam in rats.
基金supported by the National Natural Science Foundation of China(20906059,21272145)the Shaanxi Innovative Team of Key Science and Technology(2013KCT-17)+1 种基金the Fundamental Research Funds for the Central Universities(GK201503030,GK261001095)the 111 Project,and Canada Research Chair(to CJL)
文摘Carboxylate as a promising and valuable directing group has attracted a great deal of attention.However,employing it as a traceless direction group has rarely been reported.We developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C–H functionalization followed by decarboxylation to afford the corresponding metasubstituted N-aryl benzamides,in which the carboxylate serves as a unique,removable directing group.Notably,this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides,which are much more difficult to prepare than ortho-substituted analogues.