180905-82-2Relevant academic research and scientific papers
Reductive smiles rearrangement of 1-[(5-chloro-2-Nitrophenyl)sulfonyl]-1H-pyrrole-2-carbohydrazide to 1-amino-6-chloro-2-(1H-pyrrol-2-yl)benzimidazole
Silvestri, Romano,Pifferi, Augusto,De Martino, Gabriella,Massa, Silvio,Saturnino, Carmela,Artico, Marino
, p. 2163 - 2174 (2007/10/03)
Treatment of 1-[(5-chloro-2-nitrophenyl)sulfonyl]-1H-pyrrole-2-carbohydrazide with powdered iron in glacial acetic acid afforded 1-amino-6-chloro-2-(1H-pyrrol-2-yl)benzimidazole as the sole product. This compound was also obtained by iron-acetic acid reduction of 1-(5-chloro-2-nitrophenyl)-1H-pyrrole-2-carbohydrazide. Splitting of the sulfone group occurred only in the presence of the carbohydrazide group. In fact, iron-acetic acid reduction of 5-chloro-2-nitrophenyl 2-ethoxycarbonyl-1H-pyrrol-1-yl sulfone gave the expected 2-amino-5-chlorophenyl 2-ethoxycarbonyl-1H-pyrrol-1-yl sulfone. Treatment of this compound with hydrazine yielded the corresponding carbohydrazide, which failed cyclization when reacted with phosphorus pentoxide. Formation of 7-chloropyrrolo[1,2-b] [1,2,5]benzothiadiazepin-11(10H)-one 5,5-dioxide with loss of hydrazine was observed when the above amino hydrazide was reacted with 2-hydroxypyridine or with glacial acetic acid.
5H-pyrrolo[1,2-b][1,2,5]benzothiadiazepines (PBTDs): A novel class of non- nucleoside reverse transcriptase inhibitors
Artico,Silvestri,Pagnozzi,Stefancich,Massa,Loi,Putzolu,Corrias,Spiga,La Colla
, p. 837 - 850 (2007/10/03)
With the aim of developing novel inhibitors of human immunodeficiency virus, various derivatives (10-17) related to 5H-pyrrolo[1,2- b][1,2,5]benzothiadiazepine (PBTD) were prepared and tested in vitro. The title tricyclic derivatives were obtained by intramolecular cyclization of the open-chain intermediate arylpyrrylsulfones, followed by N-alkylation at position 10. Among test derivatives some 10-alkyl-5H-pyrrolo[1,2- b][1,2,5]benzothiadiazepin-11(10H)-one-5,5-dioxides were found to exert potent and specific activity against HIV-1. In particular, 7-chloro derivatives 11i and j showed a potency comparable to that of nevirapine. However, when the chloro atom was shifted to the 8 position, the related products were scarcely active or totally inactive. Replacement of the pyrrole with pyrrolidine led to inactive products and the reduction of SO2 to S strongly diminished the antiviral potency. PBTD derivatives active in cell cultures were also inhibitory to the recombinant HIV-1 RT in enzyme assays, thus allowing the conclusion that PBTDs are a new class of non-nucleoside reverse transcriptase inhibitors (NNRTIs).
