“…For example, the reported works describe synthesis of alkyl thieno [3,2-b]pyrrole-5-carboxylates III with the following substituents: 2-formyl, 11,19 2-acetyl, 11 2-bromo, 28 2,6-dibromo, 11 2,3,6-tribromo, 11 2-nitro, 28 2,6-dinitro, 28 3-formyl, 19 4-benzyl, 10 4-(2-nitrobenzyl), 11,34 6-dimethylaminomethyl, 11 6-(1-piperidinylmethyl), 13 6-cyanomethyl, 11 6-formyl, 11,37 2-methyl-3-acyl, 35-37 2-methyl-3,6-diacyl, 35,37 2-methyl-4-(2-oxopropyl), 38 and 2-methyl-4-(2-oxo-2-phenylethyl). 38 Some of the mentioned esters were then hydrolyzed to the corresponding acids, which usually served as convenient starting materials in subsequent transformations, for example, for synthesis of the corresponding amides 13,18 or decarboxylated products. 18 Syntheses of several annulated heterocycles possessing the 4H-thieno [3,2-b]pyrrole moiety have been previously described, for example, thieno [2,3-b]indolizine IV, 39 5,6,7,8tetrahydro-4H-thieno[3′,2′:2,3]pyrrolo [4,5-c]pyridine V, 14 8-oxo-5,6,7,8-tetrahydrothieno[2′,3′:4,5]pyrrolo [1,2-a]pyrazine VI, 38 3H,4H,5H-thieno[3′,2′:2,3]pyridazin-4-ones VII, 11,37 and 5-oxo-6,11-dihydro-5H-benzo[e]thieno[2′,3′:4,5]pyrrolo-[1,2-a] 1,4 diazepine VIII.…”