Microwave-Assisted Expeditious Synthesis of 2-Alkyl-2-(N-arylsulfonylindol-3-yl)-3-N-acyl-5-aryl-1,3,4-oxadiazolines Catalyzed by HgCl2 under Solvent-Free Conditions as Potential Anti-HIV-1 Agents

Abstract

A series of 2-alkyl-2-(N-arylsulfonylindol-3-yl)-3-N-acyl-5-aryl-1,3,4-oxadiazolines were expeditious prepared under microwave-assisted, catalyzed by HgCl2 and solvent-free conditions. This method has the advantage of low catalyst loading and recovering catalyst, ease reaction and repaid reaction times, easy separation products and excellent yields, and more conducive to the large-scale synthesis products. Furthermore, compounds 3s, 3y, 3a′, 3b′, 3f′, 3i′, 3q′, and 3r′ exhibited more potent anti-HIV-1 activity with EC50 values of 3.35, 6.12, 3.63, 9.54, 1.79, 0.51, 3.00, and 4.01 μg/mL, and TI values of 32.66, >32.68, 31.22, 13.94, 24.27, 39.59, 26.01, and 24.51, respectively. Especially compound 3i′ displayed the highest anti-HIV-1 activity with TI values of 39.59.

Facile Stereoselective Synthesis and Structural Study of Camphor‐ and Fenchone‐Based Spirocyclic 1,3,4‐Oxadiazolines

“…[26] The effect of Lewis acids on the reaction yields has also been studied. [27] Despite the wide range of applications, it was shown in [19] that this method is not applicable for the preparation of camphor-based oxadiazolines. Spirocyclic 1,3,4-oxadiazolines could be obtained neither from camphor semicarbazone nor from acetyl and diacetyl hydrazone.…”

“…Usually this reaction is carried out by refluxing with carboxylic acids anhydrides [22–25] or in acetic anhydride/pyridine mixture [26] . The effect of Lewis acids on the reaction yields has also been studied [27] …”

A review on microwave assisted synthesis, mechanism of action and structure activity relationship of 1, 3, 4-oxadiazoleA review on microwave assisted synthesis, mechanism of action and structure activity relationship of 1, 3, 4-oxadiazole derivatives as anticancer agent derivatives as anticancer agent

“…Scheme 2 Che et al, synthesized a sequence of 2-alkyl-2-(N-arylsulfonylindol-3-yl)-3-N-acyl-5-aryl-1,3,4-oxadiazoline derivatives using microwave irradiation. N-benzenesulfonyl-3-acetylindole benzoyl hydrazone reacted with acetic anhydride, catalyzed by HgCl2 under solvent-free conditions[43].…”