Pyrazolo-1,5-benzothiazepines

Fusion of a pyrazole ring with a thiazepine nucleus results in three possible isomeric systems, one of which has a nitrogen bridgehead. Whereas this last possibility allows only one fusion, that on the d edge, 

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One patent claims the synthesis of 4,5-dihydro-ltf-pyrazolo[3,4-6][l,5]benzothiazepines (70) and their hydrochlorides. 2-Aminothiophenol (5) was refluxed in toluene with 5-chloro-4-pyrazolecarboxaldehyde (68) to give 69, which was reduced by sodium borohydride and acylated to afford 70 (Scheme 19) [78GEP(O)2707269]. 

The Ulmann reaction of 4-bromo-3-(2-aminophenyl)thiomethyl-3-pyra-zolin-5-ones (74) in a nonpolar solvent such as xylene and in the presence of a small amount of pyridine afforded 1,2,4,10-tetrahydro-3//-pyrazolo[3,4-c][l,5]benzothiazepin-3-ones (75). However, when the same reaction was... 

The synthesis of H- and 2H- pyrazolo[3,4-c][2,l]benzothiazepines has been accomplished in view to develop new derivatives with potential psychotropic activity <94JHC93>. Pyrazolemethylene-biaryl-tetrazoles (311) are highly potent antagonists of angiotensin II and their pharmacokinetic parameters in the rat have been reported <94BMC151,94cpbi617>. 

The novel fused heterocyclic system pyrazolo[4, 3 5,6]pyrido-[2,3-b]-1,5-benzoxepine (53) and its benzothiazepine analogue have been obtained by cyclisation of a substituted pyrazolo[3,4-b]-pyridine derivative. 

Tricyclic systems as compounds of potential pharmacological interest prepared by conventional cyclisation procedures include thienoanellated [l,4]benzoxazepines <94JHC1053>, pyrido[l,4] and [l,5]benzoxazepines and thiazepines <94JMCS19>, and IH- and 2H-pyrazolo[3,4-c][2,l]benzothiazepines <94JHC93>. A number of... 

K. Arya, B. Prabhakar, Ionic liquid confined zeolite system an approach towards water mediated room temperature synthesis of spiro[pyrazolo[3,4-e]benzothiazepines]. Green Chem. 15 (2013) 2885-2894. 

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