Regioselective Synthesis of Novel N2- and N4-Substituted 7-Methylpyrazolo[4,5-e][1,2,4]thiadiazines

• Main Authors: Salvador Vega, Maria Teresa Molina, Wenfang Xu, Niangen Chen, Renzhang Yan, Xinyong Liu
• Format: Article
• Language: English
• Published: MDPI AG 2006-11-01
• Series: Molecules
• Subjects: Pyrazolothiadiazines; regioselectivity; synthesis; alkylation; one-pot reaction
• Online Access: http://www.mdpi.com/1420-3049/11/11/827/
• ISSN: 1420-3049

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 6and 7 were prepared by regioselective N-alkylation of 5 with different molar ratios ofNaH and alkyl halides. Based on the regioselective alkylation conditions found a facileone-pot synthesis of N2,N4-disubstituted pyrazolo[4,5-e][1,2,4] thiadiazines 8 wasdeveloped. The structures of the newly synthesized compounds were confirmed by IR,1H-NMR, 13C-NMR and MS spectral analysis.