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c. Synthesis of 2-carbethoxy-3-amino-4-methoxybenzo(b)thiophene 33 (Ixvii)Part-IResults and DiscussionReaction of 2-nitro-6-methoxy benzonitrile 14 and methyl thioglycolate 16 under basiccondition and with continuous stirring at 0 o C gave the title compound in high yield(Scheme-13).CNO 2 N NO 2ONO 2KCNCH 3 OH13 14HSOHDry HClMeOHHSOO15O16CNOONO 2+HSODMFOOSNH 2O14 16 IxviScheme-133.1.2e. Synthesis of 5-amino-4-carboxamido-3-(methylthio)-1-phenylpyrazole 34 (Ixv)The 5-amino-4-carboxamido-3-(methylthio)-1-phenylpyrazole was synthesized by seriesof steps as under. The ethyl cyanoacetate 17 and ammonia were reacted to getcyanoacetamide 18. Then cyanoacetamide and carbon disulfide were reacted in presenceof aq. KOH to form the potassium dithiolate salt 19, which was then S-methylated withdimethyl sulphate to yield ethyl-2,2-di-(methylthio)methylene cyanoacatamide 20. Theethyl-2,2-di-(methylthio)methylene cyanoacetamide was then refluxed with phenylhydrazine 21 in ethanol to form 5-amino-4-carboxamide-3-(methylthio)pyrazole Ixvii asa sole product (Scheme-14).75