A novel facile route for the introduction of 5-amino and 5-alkylamino substituents into 1-aryltetrazoles has been developed. A range of 5-amino-1-aryltetrazoles was obtained directly from the corresponding 1-aryltetrazoles in one pot by consecutive ring-opening, azidation and intramolecular cyclization. 5-Alkylamino-1-aryltetrazoles were formed by a similar mechanism from 1,4-disubstituted tetrazolium salts. An influence of the nature of aryl substituents and reaction conditions on the regioselectivity of the intramolecular cyclization of intermediate guanyl azides is revealed.
Sulfocoumarins as dual inhibitors of human carbonic anhydrase isoforms IX/XII and of human thioredoxin reductase
作者:Mikhail Krasavin、Raivis Žalubovskis、Aiga Grandāne、Ilona Domračeva、Petr Zhmurov、Claudiu T. Supuran
DOI:10.1080/14756366.2020.1712596
日期:2020.1.1
acting as inhibitors of human carbonic anhydrase (CA, EC 4.2.1.1) cancer-associated isoforms hCA IX and - hCA XII is being able to also inhibitthioredoxinreductase was verified and confirmed. The dual targeting of two cancercell defence mechanisms, i.e. hypoxia and oxidative stress, may both contribute to the observed antiproliferative profile of these compounds against many cancercell lines. This
Efficient and rapid synthesis of 1-substituted-1H-1,2,3,4-tetrazoles in the acidic ionic liquid 1-n-butylimidazolium tetrafluoroborate
作者:Taterao M. Potewar、Shafi A. Siddiqui、Rajgopal J. Lahoti、Kumar V. Srinivasan
DOI:10.1016/j.tetlet.2007.01.050
日期:2007.3
An efficient synthesis leading directly to 1-substituted-1H-1,2,3,4-tetrazoles from easily available amines and sodium azide in stoichiometric proportions using a room-temperature ionic liquid, namely, 1-n-butylimidazolium tetrafluoroborate in excellent yields is described. The inherent Bronsted acidity and high polarity of the IL results in a significant enhancement in the reaction rate. (c) 2007 Elsevier Ltd. All rights reserved.
A novel synthesis of 1-aryl tetrazoles promoted by employing the synergy of the combined use of DMSO and an ionic liquid as the solvent system at ambient temperature
作者:Satish N. Dighe、Kishor S. Jain、Kumar V. Srinivasan
DOI:10.1016/j.tetlet.2009.08.063
日期:2009.11
The synergy of the combined use of DMSO and an ionic liquid viz. (bbim)*Br- has brought about a mild, convenient, efficient, and rapid protocol for the synthesis of 1-substituted-1H-1,2,3,4-tetrazoles via the condensation of amines, triethyl orthoformate, and sodium azide at ambient temperature in excellent isolated yields (85-90%). The inherent Bronsted acidity of ionic liquid and high polarity of both IL and DMSO resulted in a significant enhancement in the reaction rate. (C) 2009 Elsevier Ltd. All rights reserved.
Synthesis of 6-tetrazolyl-substituted sulfocoumarins acting as highly potent and selective inhibitors of the tumor-associated carbonic anhydrase isoforms IX and XII
作者:Aiga Grandane、Muhammet Tanc、Raivis Zalubovskis、Claudiu T. Supuran
DOI:10.1016/j.bmc.2014.01.043
日期:2014.3
A series of 6-substituted sulfocoumarins incorporating substituted-1,2,3,4-tetrazol-5-yl moieties were synthesized by reaction of 6-iodo-sulfocoumarin and the corresponding tetrazole via the CH activation reaction. The new sulfocoumarins incorporating alkyl and substituted aryl moieties at the 1-position of the tetrazole, were investigated for the inhibition of four human (h) carbonic anhydrase (hCA, EC 4.2.1.1) isoforms, the cytosolic hCA I and II; and the transmembrane, tumor-associated hCA IX and XII. The tetrazole-substituted sulfocoumarins did not inhibit the ubiquitous, off-target cytosolic isoforms (K(I)s > 10 mu M) but showed effective inhibition against the two transmembrane CAs, with KIs ranging from 6.5 to 68.6 nM against hCA IX, and between 4.3 and 59.8 nM against hCA XII. As hCA IX and XII are validated anti-tumor targets, such prodrug, isoform-selective inhibitors as the sulfocoumarins reported here, may be useful for identifying suitable drug candidates for clinical trials. (C) 2014 Elsevier Ltd. All rights reserved.