An efficient domino process for the synthesis of thioflavanones has been described using a copper catalyst without addition of any external ligand. A variety of thioflavanones have been synthesized from easily accessible 2'-iodochalcones or 2'-bromochalcones in excellent yield through in situ incorporation of sulfur using xanthate as an odorless sulfur source. This domino process proceeds through Cu-catalyzed C(aryl)-S bond formation by the coupling reaction of xanthate with 2'-halochalcones followed by C-S bond cleavage of thioester then S-C bond formation by intramolecular Michael addition.

This review presents the metal-catalyzed C–S bond-formation reaction to access organosulfur compounds using various sulfur surrogates with an extended discussion on the reaction mechanism, regioselectivity of product and pharmaceutical application.

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This paper presents a stochastic model to simulate spatial distribution of slip on the rupture plane for large earthquakes (M w > 7). A total of 45 slip models coming from the past 33 large events are examined to develop the model. The model has been developed in two stages. In the first stage, effective rupture dimensions are derived from the data. Empirical relations to predict the rupture dimensions, mean and standard deviation of the slip, the size of asperities and their location from the hypocentre from the seismic moment are developed. In the second stage, the slip is modelled as a homogeneous random field. Important properties of the slip field such as correlation length have been estimated for the slip models. The developed model can be used to simulate ground motion for large events.

Copper-catalyzed one-pot synthesis of various 2-arylthiochromenones is developed using xanthate as an odorless sulfur source from easily acquirable 2′-halochalcones. This methodology demonstrates that the cross-coupled product thiochromanone synthesized from 2′-halochalcones (upstream reaction) is oxidized to thiochromenone (downstream reaction) in the same pot using waste byproduct (KI) of the first step as powerful oxidant molecular iodine (I 2 ). This one-pot synthesis has been further extended for the synthesis of 3,3′-methylenebisthioflavone using dimethyl sulfoxide (DMSO) as solvent and methylene source.

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Anticaries bioactive compounds of A. aspera with higher QS response regulator binding energy, low toxicity and optimal pharmacokinetic properties were revealed. These compounds with possible QQ ability hold the potential for use as anticaries drug leads and antibiofilm preventative medicine.

An efficient protocol is described for the synthesis of 2-acylbenzo[b]thiophenes from easily accessible 2-iodochalcones through α-C-H functionalization using Cu(OAc) catalyst and xanthate as sulfur source. Less reactive 2-bromochalcones also yielded the corresponding 2-acylbenzothiophenes in good yield. The reaction proceeds via in situ incorporation of sulfur followed by copper-catalyzed cyclization to generate 2-acylbenzothiophenes without external acyl source. The synthetic importance is showcased by synthesis of 1-(5-hydroxybenzothiophene-2-yl)ethanone, which is a known pre-mRNA splicing modulator.