Click-chemistry-inspired synthesis of new series of 1,2,3-triazole fused chromene with glucose triazole conjugates: Antibacterial activity assessment with molecular docking evaluation.

A series of new 1,2,3-triazole fused chromene based glucose triazole conjugates were synthesized from chromene fused 1,2,3-triazolyl extended alkyne and 2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl azide in good to excellent yield by a copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The major advantages include mild reaction conditions, high yield, good substrate scope, and shorter reaction time. The antibacterial efficacy of the compounds were assessed in vitro against human pathogenic Gram-negative E.

Design and synthesis of 1,2-dihydroquinoline/chromene fused sugar triazole frameworks by copper-catalyzed one-pot click and intramolecular arylation reactions.

Expedient copper-catalyzed one-pot click and intramolecular arylation reactions have been developed for the synthesis of 1,2-dihydroquinoline/chromene-fused triazoles with varying sugar functionalities. It has been observed that the additive TMEDA greatly facilitates this copper-catalyzed cyclization. This reaction involves two mechanistically distinct reactions an atom-economical click reaction and a direct arylation of a sugar triazole.

Recent developments in the synthesis of hybrid antimalarial drug discovery.

In this 21 century, Malaria remains a global burden and causes massive economic trouble to disease-endemic nations. The control and eradication of malaria is a major challenge that requires an urgent need to develop novel antimalarial drugs. To overcome the aforementioned situation, several researchers have given significant effort to develop hybrid antimalarial agents in the search for new antimalarial drugs.

Recent advances on synthesis of C-glycosides.

In recent years, C-glycosides have emerged as significant building blocks for many naturally occurring alkaloids and pharmaceutically active drug molecules. Therefore, significant efforts have been devoted to the construction of structurally important C-glycosidic linkages in carbohydrate compounds. Herein, we have summarized the recent developments of diverse synthesis of C-glycoside core between the time period from 2019 to 2022 focusing on different catalytic strategies, such as (i) transition-metal, and (ii) metal-free catalytic approaches.

Base mediated green synthesis of enantiopure 2-C-spiro-glycosyl-3-nitrochromenes.

A novel green synthetic methodology has been developed to obtain enantiopure (2S)-2-C-spiro-glycosyl-3-nitrochromenes following the oxa-Michael-aldol condensation reaction of sugar derived 3-C-vinyl nitro olefins with substituted salicylaldehydes using Et3N as a base under neat conditions at rt-40 °C. The stereochemistry of the product is confirmed by a single crystal X-ray study. Several advantages are associated with this protocol such as cost effectiveness, easy accessibility, short reaction time, high yields, wide substrate scope and high enantiopurity.

Diastereoselective synthesis of novel spiro indanone fused pyrano[3,2-]chromene derivatives following hetero-Diels-Alder reaction and anticancer studies.

The development of concise methods for the synthesis of small functionalised spirocyclic molecules is important in the search of new bioactive molecules. To contribute this, here we represent a diastereoselective oxa-hetero-Diels-Alder reaction for the synthesis of novel spiro indanone fused pyrano[3,2-]chromene derivatives and studied their anticancer activities. Using previously less explored cyclic ketone indane-1,3-dione and 3-vinyl-2-chromene derivatives, we obtained novel spiro-heterocyclic frameworks at the interphase between "drug-like" molecules and natural products.

14,15-Epoxyeicosa-5,8,11-trienoic Acid (14,15-EET) surrogates: carboxylate modifications.

The cytochrome P450 eicosanoid 14,15-epoxyeicosa-5,8,11-trienoic acid (14,15-EET) is a powerful endogenous autacoid that has been ascribed an impressive array of physiologic functions including regulation of blood pressure. Because 14,15-EET is chemically and metabolically labile, structurally related surrogates containing epoxide bioisosteres were introduced and have become useful in vitro pharmacologic tools but are not suitable for in vivo applications. A new generation of EET mimics incorporating modifications to the carboxylate were prepared and evaluated for vasorelaxation and inhibition of soluble epoxide hydrolase (sEH).

Organocatalytic tandem Michael addition reactions: A powerful access to the enantioselective synthesis of functionalized chromenes, thiochromenes and 1,2-dihydroquinolines.

Enantioselective organocatalysis has become a field of central importance within asymmetric chemical synthesis and appears to be efficient approach toward the construction of complex chiral molecules from simple achiral materials in one-pot transformations under mild conditions with high stereocontrol. This review addresses the most significant synthetic methods reported on chiral-amine-catalyzed tandem Michael conjugate addition of heteroatom-centered nucleophiles to α,β-unsaturated compounds followed by cyclization reactions for the enantioselective construction of functionalized chiral chromenes, thiochromenes and 1,2-dihydroquinolines in optically enriched forms found in a myriad of bioactive natural products and synthetic compounds.

Design and Synthesis of 3,5-Disubstituted 1,2,4-Oxadiazole Containing Retinoids from a Retinoic Acid Receptor Agonist.

We previously synthesized novel retinoid libraries, and after screening for bioactivity found one compound BT10 that functions as a specific agonist for retinoic acid receptors. This lead compound was further derivatized using SAR and LRD to obtain 3,5-disubstituted-1,2,4-oxadiazole-containing retinoids. The new oxadiazole (amide bioisosters)-containing retinoids (compounds 1, 2, 3, 4, 5, and 6) were synthesized in 42-65% yield by reacting with (E)-4-((3-ethyl,2-4,4,4-trimethylcyclohex-2-enylidene)methyl)benzoic acid and phenyl substituted amidoxime in DMF using CDI as the coupling reagent.

Synthesis of function-oriented 2-phenyl-2H-chromene derivatives using L-pipecolinic acid and substituted guanidine organocatalysts.

Organocatalytic domino oxa-Michael/aldol reactions between salicylaldehyde with electron deficient olefins are presented. We screened guanidine, 1,1,3,3-tetramethylguanidine (TMG) and L-pipecolinic acid as organocatalysts for this transformation. 3-Substituted 2-phenyl-2H-chromene derivatives are synthesized with high yields and with poor enantioselectivity (5-17% ee) using L-pipecolinic acid while TMG works well with cinnamaldehyde without using co-catalyst.