Intramolecular cyclization of N-alkoxyl amines are studied for the stereoselective preparation of 2, 4-disubstituted pyrrolidine derivatives. Reduction of oximes under acidic conditions by NaBH3CN afforded the corres...Intramolecular cyclization of N-alkoxyl amines are studied for the stereoselective preparation of 2, 4-disubstituted pyrrolidine derivatives. Reduction of oximes under acidic conditions by NaBH3CN afforded the corresponding nucleophilic hydroxylamine derivatives, which subsequently cyclized via SN2' mechanism to give the desired N-alkoxyl pyrrolidines.展开更多
On the basis of the Zaleplon structure, novel pyrazolo[l,5-a]pyrimidines were designed and prepared for studies on their hypnotic activity. This paper reported the synthesis of twelve new 5-methyl-7-substituted-pyrazo...On the basis of the Zaleplon structure, novel pyrazolo[l,5-a]pyrimidines were designed and prepared for studies on their hypnotic activity. This paper reported the synthesis of twelve new 5-methyl-7-substituted-pyrazolo[1,5-a]pyrimidine-3-carbonitrile derivatives by using simple starting materials such as propane dinitrile and triethyl orthoformate. The structures of the derived target compounds were confirmed by their IR and 1H-NMR spectroscopic data. The preliminary pharmacological evaluations indicated that some compounds showed hypnotic activity, while derivative 1c was the most polent one.展开更多
基金KZ acknowledges supports from the National Young Scholar Award of the NSFC(#30125043)from the Chung Kong Scholars Program administered by the Ministry of Education,PRC and the Li Ka Shing Foundation,Hong Kong.
文摘Intramolecular cyclization of N-alkoxyl amines are studied for the stereoselective preparation of 2, 4-disubstituted pyrrolidine derivatives. Reduction of oximes under acidic conditions by NaBH3CN afforded the corresponding nucleophilic hydroxylamine derivatives, which subsequently cyclized via SN2' mechanism to give the desired N-alkoxyl pyrrolidines.
文摘On the basis of the Zaleplon structure, novel pyrazolo[l,5-a]pyrimidines were designed and prepared for studies on their hypnotic activity. This paper reported the synthesis of twelve new 5-methyl-7-substituted-pyrazolo[1,5-a]pyrimidine-3-carbonitrile derivatives by using simple starting materials such as propane dinitrile and triethyl orthoformate. The structures of the derived target compounds were confirmed by their IR and 1H-NMR spectroscopic data. The preliminary pharmacological evaluations indicated that some compounds showed hypnotic activity, while derivative 1c was the most polent one.