A Diversified Assembly of 1,2,4-Oxadiazol-3-amines: Metallic Thiophile Catalyzed Chemoselective One-Pot Reaction of Aryl Isothiocyanates, Amidines/Guanidines, and Hydroxylamine
摘要:
An efficient one-pot synthesis of 1,2,4-oxadiazol-3-amines from simple starting materials, isothiocyanates, amidines/guanidines, and hydroxylamine, is described. The reaction is facilitated by metallic-thiophile-assisted desulfurization of in situ formed amidino- or guanidinothiourea to give chemoselectively N-hydroxyguanidine intermediates that give exclusively various 1,2,4-oxadiazol-3-amines in good to excellent yields. The reaction mechanistic pathway may proceed through an intramolecular 5-exotrig cyclization.
A convenient one-pot synthesis of trisubstituted 1,3,5-triazines through intermediary amidinothioureas
作者:Jitendra C. Kaila、Arshi B. Baraiya、Amit N. Pandya、Hitesh B. Jalani、V. Sudarsanam、Kamala K. Vasu
DOI:10.1016/j.tetlet.2010.01.034
日期:2010.3
A thiophile-promoted one-potsynthesis of trisubstituted 1,3,5-triazines starting from isothiocyanates, N,N-diethylamidines, and carbamidines has been studied. The reaction proceeds through the formation of intermediary amidinothioureas, which react with carbamidines in the presence of mercury(II) chloride to generate the desired 1,3,5-triazines in good to moderate yields (40–70%).
Mercury(II) Chloride-Mediated Desulphurization of Amidinothioureas: Synthesis and Antimicrobial Activity of 3-Amino-1,2,4-triazole Derivatives
作者:Swapnil G. Yerande、Chetna D. Baviskar、Kiran M. Newase、Wei Wang、Kan Wang、Alexander Dömling
DOI:10.1002/jhet.1890
日期:2014.11
The synthesis of 3‐amino‐1,2,4‐triazole via mercury(II) chloride‐mediated cyclization of amidinothiourea is described. This procedure offers a general and efficient route to synthesize the title compound by 3 + 2annulation reaction. On the basis of the literature precedence, the mechanism for the formation of 3‐amino‐1,2,4‐triazole is proposed. When the synthesized compounds were tested for their
Discovery of 2-aminoimidazole and 2-amino imidazolyl-thiazoles as non-xanthine human adenosine A<sub>3</sub>receptor antagonists: SAR and molecular modeling studies
作者:Amit N. Pandya、Arshi B. Baraiya、Hitesh B. Jalani、Dhaivat Pandya、Jitendra C. Kaila、Sonja Kachler、Veronica Salmaso、Stefano Moro、Karl-Norbert Klotz、Kamala K. Vasu
DOI:10.1039/c7md00643h
日期:——
le derivatives was synthesized using a 2-chloro trityl resin. The generated compound library was tested against all the humanadenosinereceptors subtypes. The 2-aminoimidazole derivatives (6a–6l) showed weak to moderate affinity towards the humanadenosinereceptors. Further modification to 2-aminoimidazolyl-thiazole derivatives (12a–12l) resulted in an improvement of affinity at adenosineA1, A2A
Design, synthesis and characterization of novel 2-(2,4-disubstituted-thiazole-5-yl)-3-aryl-3H-quinazoline-4-one derivatives as inhibitors of NF-κB and AP-1 mediated transcription activation and as potential anti-inflammatory agents
作者:Rajan S. Giri、Hardik M. Thaker、Tony Giordano、Jill Williams、Donna Rogers、Vasudevan Sudersanam、Kamala K. Vasu
DOI:10.1016/j.ejmech.2008.10.031
日期:2009.5
A series of 2-(2,4-disubstituted-thiazole-5-yl)-3-aryl-3H-quinazoline-4-one derivatives were designed and synthesized. Synthesized molecules were further evaluated for their inhibitory activity towards transcription factors NF-kappa B and AP-1 mediated transcriptional activation in a cell line based in vitro as well as for their anti-inflammatory activity in in vivo model of acute inflammation. This series provides us with selective and dual inhibitors of NF-kappa B and AP-1 mediated transcriptional activation which also exhibit significant efficacy in in vivo model of inflammation. Two of the compounds 9m and 9o turned out to be the most promising dual inhibitors of NF-kappa B and AP-1 mediated transcriptional activation with an IC50 of 3.3 mu M for both. 9n (IC50 = 5.5 mu M) and 9p (IC50 = 5.5 mu M) emerged as selective inhibitors of NF-kappa B mediated transcriptional activation and 9c (IC50 = 5.5 mu M) and 9d (IC50 = 5.5 mu M) were found to be more selective inhibitor of AP-1 mediated transcriptional activity. Though the relationship between the activities shown by these compounds in in vivo and in vitro model is still to be established, these results suggest the suitability of the designed molecular framework as a potential anti-inflammatory molecular framework which also exhibits the inhibitory activity towards NF-kappa B and AP-1 mediated transcriptional activation. This will be worth studying further to explore its complete potential particularly in chronic inflammatory conditions. The structure activity relationship (SAR) of this series has been discussed herein. (C) 2008 Elsevier Masson SAS. All rights reserved.
A facile synthesis of structurally novel 1-aryl-2-arylamino-4-alkyl/phenyl-5-aroyl-1H-imidazoles from amidinothioureas
作者:Jitendra C. Kaila、Arshi B. Baraiya、Kamala K. Vasu、V. Sudarsanam
DOI:10.1016/j.tetlet.2008.10.012
日期:2008.12
We report here a convenient and efficient two-step synthesis of 1-aryl-2-arylamino-4-alkyl/phenyl-5-aroyl-1H-imidazoles from easily available amidinothioureas. Guanylation of amidinothioureas 1 using mercury(II) chloride as a thiophile yielded amidinoguanidines 2, which reacted with various phenacyl bromides under mild conditions to afford the corresponding diversely functionalized imidazoles 3 in moderate to good yields. (C) 2008 Elsevier Ltd. All rights reserved.