A comprehensive review on natural occurrence, synthesis and biological activities of glycolipids.

Glycolipids are ubiquitous and biologically important molecules and are involved in diverse biological functions and exhibit biosurfactant applications due to their surface-active and biodegradability properties. Despite showing a wide range of biological functions, not enough commercial exploitation has been taken place. Possible reasons for this could be the lack of focus or commercially viable processes for isolation/purification, as these glycolipids are found to be complex mixtures in their respective natural sources. Keeping these complexities in view, in this review, we focused on natural occurrences, including plants, marine micro algae, microorganisms, and salient features of various chemical methods, including glycosylation methods for the synthesis of different types of glycolipids. Further, this review significantly summarises the biological evaluation of a diverse class of glycolipids isolated and/or synthesized either by partial or total synthesis.

Synthesis and biological evaluation of 5-fatty-acylamido-1, 3, 4-thiadiazole-2-thioglycosides.

In the present study, the synthesis of 1, 3, 4-thiadiazole-based thioglycosides were accomplished in good yields with employing a convergent synthetic route. The starting material 5-amino-1, 3, 4-thiadiazole-2-thiol and followed by a series of 5-fatty-acylamido-1, 3, 4-thiadiazole-2-thiols (4a-4j) were synthesized with different fatty acid chlorides. The glycosylation of compounds 4a-4j were achieved with trichloroacetimidate methodology. Antimicrobial and cytotoxicity activities of title compounds were evaluated. Among the entire compounds lauric acid and myristic acid derivatives showed good and moderate antimicrobial activity. In case of cytotoxicity results of compounds 8a-8j and 9a-9j, the acetate protected short chain (C6:0, C8:0, C10:0) compounds and the free hydroxyl long chain saturated (C16:0, C18:0) and unsaturated (C18:1, C22:1) compounds exhibited good activity against different cancer cell lines. Further, the free hydroxyl compounds 9a, 9c-9j did not show any toxicity towards normal CHO-K1 cell line whereas acylated compounds 8a-8j exhibited toxicity.