Novel Syntheses of 2,3-Dihydro-1,5-benzothiazepin-4(5H)-ones and 2H-1,4-Benzothiazin-3(4H)-ones
摘要:
Nucleophilic additions of alpha -mercaptoalkanoate esters, and beta -mercaptoalkanoate acids to benzoquinone diimines, followed by cyclization with trifluoroacetic acid or 1,3-dicyclohexylcarbodiimide (DCC), provide novel, high-yielding syntheses of 2H-1,4-benzothiazin-3(4H)-ones (3a-f) and 2,3-dihydro-1,5-benzothiazepin-4(5H)-ones (5a-c), respectively.
Novel Syntheses of 2,3-Dihydro-1,5-benzothiazepin-4(5H)-ones and 2H-1,4-Benzothiazin-3(4H)-ones
摘要:
Nucleophilic additions of alpha -mercaptoalkanoate esters, and beta -mercaptoalkanoate acids to benzoquinone diimines, followed by cyclization with trifluoroacetic acid or 1,3-dicyclohexylcarbodiimide (DCC), provide novel, high-yielding syntheses of 2H-1,4-benzothiazin-3(4H)-ones (3a-f) and 2,3-dihydro-1,5-benzothiazepin-4(5H)-ones (5a-c), respectively.
Structural assignment of regioisomeric 3-[2- or 5-anilino-2-(alkylamino)phenyl]propanoic acids, 2H-1,4-benzothiazin-3(4H)-ones and 2,3-dihydro-1,5-benzothiazepin-4(5H)-ones by 1D NOE and gHMBC NMR techniques
作者:Alan R. Katritzky、Novruz G. Akhmedov、Mingyi Wang、Charles J. Rostek、Peter J. Steel
DOI:10.1002/mrc.1373
日期:2004.7
techniques (APT, DEPT, NOE difference, COSY, NOESY, HETCOR and gHMQC, gHMBC). Temperature‐dependent 1H NMR spectra of 8‐anilino‐5‐(4‐methyl‐2‐pentyl)‐2,3‐dihydro‐1,5‐benzothiazepin‐4(5H)‐one (18) indicated a free energy of activation (ΔG‡) of ca 17 kcal mol−1 for interconversion between rotamers. The 1H and 13C NMR spectra of 20 and 22 containing two chiral centers exhibit duplication of several signals
Novel Syntheses of 2,3-Dihydro-1,5-benzothiazepin-4(<i>5H</i>)-ones and 2<i>H</i>-1,4-Benzothiazin-3(4<i>H</i>)-ones
作者:Alan R. Katritzky、Herman H. Odens、Suoming Zhang、Charles J. Rostek、Otto W. Maender
DOI:10.1021/jo0101959
日期:2001.10.1
Nucleophilic additions of alpha -mercaptoalkanoate esters, and beta -mercaptoalkanoate acids to benzoquinone diimines, followed by cyclization with trifluoroacetic acid or 1,3-dicyclohexylcarbodiimide (DCC), provide novel, high-yielding syntheses of 2H-1,4-benzothiazin-3(4H)-ones (3a-f) and 2,3-dihydro-1,5-benzothiazepin-4(5H)-ones (5a-c), respectively.