Furo-l,5-benzothiazepines

9-Dihydro-1 //, 3//-furo[3,4-6][l, 5]benzothiazepin-1 -ones (33) were synthesized in good yields (54-92%) by treatment of 2-aminothiophenol (5) with butenolides 32 in ethanol in the presence of concentrated hydrochloric 

10-Dihydro-l.//,3/f-furo[3,4-c][l, 5]benzothiazepin-l-ones (39) have been obtained by the heteroannelation reaction between 5 and 3-arylmeth- 

As is the case with furo derivatives, the fusion of a thiophene ring can occur only at edges b and c of the thiazepine ring otherwise, a heterocyclic ring with two heteroatoms will be obtained. Much work has appeared on the thienobenzothiazepine system and its neuropharmacological activity since its first synthesis was reported in 1968. 

Several patents report the synthesis of thieno[2,3-6][l, 5]benzothiazepin-4(5//)-ones (45) as potential antidepressant agents. These derivatives were synthesized from 2-(2-thienylthio)anilines (40), which were converted into the corresponding isocyanates 44 by reaction with COCl2 and then cyclized by treatment with A1C13. /V-Dialkylaminoalkyl derivatives 46 were pre- 

The synthesis of thieno[3,4-6][ 1,5]benzothiazepin-10(9/7)-ones (60) was carried out by cyclizing mercaptans 59 in the presence of polyphosphoric acid the reaction afforded compounds 60 and benzothiazoles 61 in approximately equal amounts. Lactams 60 were transformed into 10-piperazinyl derivatives 63 directly on treatment in refluxing toluene with piperazines or through the formation of iminochloride intermediates 62, which then reacted with an excess of piperazines under the same experimental 

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