Regioselective synthesis of novel N2- and N4-substituted 7-methylpyrazolo[4,5-e][1,2,4]thiadiazines

Xinyong Liu; Renzhang Yan; Niangen Chen; Wenfang Xu; Maria Teresa Molina; Salvador Vega

doi:10.3390/11110827

Regioselective synthesis of novel N2- and N4-substituted 7-methylpyrazolo[4,5-e][1,2,4]thiadiazines

Molecules. 2006 Nov 1;11(11):827-36. doi: 10.3390/11110827.

Authors

Xinyong Liu¹, Renzhang Yan, Niangen Chen, Wenfang Xu, Maria Teresa Molina, Salvador Vega

Affiliation

¹ Institute of Medicinal Chemistry, School of Pharmacy, Shandong University, Jinan 250012, PR China. xinyongl@sdu.edu.cn

Abstract

The new compound 7-methylpyrazolo[4,5-e][1,2,4]thiadiazin-3(2H,4H)-one1,1-dioxide (5) was synthesized and its novel mono N2- or N4-substituted derivatives 6 and 7 were prepared by regioselective N-alkylation of 5 with different molar ratios of NaH and alkyl halides. Based on the regioselective alkylation conditions found a facile one-pot synthesis of N2,N4-disubstituted pyrazolo[4,5-e][1,2,4] thiadiazines 8 was developed. The structures of the newly synthesized compounds were confirmed by IR,(1)H-NMR, (13)C-NMR and MS spectral analysis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Alkylation
Pyrazoles / chemical synthesis*
Pyrazoles / chemistry
Stereoisomerism
Thiadiazines / chemical synthesis*
Thiadiazines / chemistry

Substances

Pyrazoles
Thiadiazines