On the application of knoevenagel condensation for the synthesis of benzylidene benzothiazine compounds and structural study

[摘要] The synthesis and physico-chemical properties of new 6-acetylamino or 6-benzoyl-amino 2-benzylidene-4-methyl-4H-benzo[1,4]thiazin-3-ones and 6-benzoylamino or 6-nitro 2-benzylidene-4H-benzo[1,4]thiazin-3-ones are described. These benzylidene benzothiazine compounds were prepared by the Knoevenagel condensation with benzaldehydes. The configurations and conformations of benzylidene benzothiazine derivatives were optimised using the semi-empirical method AM1.

[学科分类] 化学（综合）

[关键词] benzothiazines;benzylidene benzothiazines;AM1 conformational and configurational analysis.