Synthesis of Isomeric Isothiazolo[4′,3′:4,5]- and Isothiazolo[4′,5′:4,5]thieno[3,2‑<i>b</i>]pyrano[2,3‑<i>d</i>]pyridines by Combination of Domino Reactions

Isothiazolothienopyridines have been prepared by a domino reaction (the SN2 reaction → the Thorpe–Ziegler reaction → the Thorpe–Guareschi reaction type) from disodium 4-cyanoisothiazole-3,5-dithiolate. By changing the order of addition of the alkylation reagents in the reaction with disodium 4-cyanoisothiazole-3,5-dithiolate both possible isomers of the isothiazolothienopyridines are synthesized. These isomers were further used in three-component domino reaction (the Knoevenagel reaction → the Michael reaction → the hetero-Thorpe–Ziegler reaction type) to obtain wide range of isomeric isothiazolothienopyranopyridines.异噻唑并噻吩并吡啶（Isothiazolothienopyridines）类化合物可由4-氰基异噻唑-3,5-二硫醇二钠盐为起始原料，通过依次经历双分子亲核取代（SN2）反应→索普-齐格勒（Thorpe–Ziegler）反应→索普-盖雷希（Thorpe–Guareschi）反应类型的多米诺反应制备得到。通过改变与4-氰基异噻唑-3,5-二硫醇二钠盐反应时烷基化试剂的加料顺序，可合成得到异噻唑并噻吩并吡啶的两种可能的区域异构体。将上述异构体进一步应用于包含克脑文盖尔（Knoevenagel）反应→迈克尔（Michael）加成反应→杂环索普-齐格勒（hetero-Thorpe–Ziegler）反应类型的三组分多米诺反应中，即可获得一系列结构多样的异噻唑并吡喃并吡啶（Isothiazolothienopyranopyridines）类异构体产物。