Shi-Meng Wang

Palladium-catalyzed Mizoroki–Heck-type reactions of [Ph2SRfn][OTf] with alkenes at room temperature

The first Pd-catalyzed Mizoroki-Heck-type reaction of [Ph2SRfn][OTf] with alkenes is described. The reaction of [Ph2SRfn][OTf] (Rfn = CF3, CH2CF3) with alkenes in the presence of 10 mol% Pd[P(t-Bu)3]2 and TsOH at room temperature provided the corresponding phenylation products in good to high yields. The bases that benefit the traditional Mizoroki-Heck reactions severely inhibited the transformation with [Ph2SRfn][OTf], whereas acids significantly improved the reaction. This protocol supplies a new class of cross-coupling partners for Mizoroki-Heck-type reactions and gains important insights into the reactivity of phenylsulfonium salts either with or without fluorine-containing alkyl groups as the promising phenylation reagents in organic synthesis.

Palladium-Catalyzed Arylation of Arylboronic Acids with Yagupolskii–Umemoto Reagents

A Pd-catalyzed Suzuki cross-coupling of arylboronic acids with Yagupolskii-Umemoto reagents was explored. In contrary to trifluoromethylations, the Pd-catalyzed reaction of R-B(OH)2 and [Ar2 SCF3 ](+) [OTf](-) provided the arylation products (R-Ar) in good to high yields. The reaction confirms that the S-Ar bonds of [Ar2 SCF3 ](+) [OTf](-) can be readily cleaved in the presence of Pd complexes. The relatively electron-poor aryl groups of asymmetric [Ar(1) Ar(2) SCF3 ](+) [OTf](-) salts are more favorably transferred compared to the electron-rich ones. This reaction represents the first report of utilization of [Ar2 SCF3 ](+) [OTf](-) as arylation reagents in organic synthesis.

Sonogashira Reaction Using Arylsulfonium Salts as Cross-Coupling Partners

Triarylsulfonium, alkyl- and fluoroalkyl(diaryl)sulfonium, and aryl(dialkyl)sulfonium triflates are successfully used as a new family of cross-coupling participants in the Sonogashira reaction as aryldiazonium, diaryliodonium, and tetraphenylphosphonium salts. It was found that terminal alkynes reacted mildly with triarylsulfonium or (2,2,2-trifluoroethyl)diphenylsulfonium triflate at room temperature under Pd- and Cu-cocatalysis to give the corresponding arylalkynes in up to >99% yield. This protocol represents the first use of arylsulfonium salts as cross-coupling partners in the Pd/Cu-catalyzed Sonogashira reaction.

Chemoselective synthesis of diaryl disulfides via a visible light-mediated coupling of arenediazonium tetrafluoroborates and CS2

A highly efficient and chemoselective method for the synthesis of diaryl disulfides is developed via a visible light-promoted coupling of readily accessible arenediazonium tetrafluoroborates and CS2. This practical and convenient protocol provides a direct pathway for the assembly of a series of disulfides in an environmentally friendly manner with good to excellent yields.

Recent Development of Sulfonyl or Sulfonamide Hybrids as Potential Anticancer Agents: A Key Review

Cancer is the second leading cause of death worldwide. There is always a huge demand for novel anticancer drugs and diverse new natural or synthetic compounds are developed continuously by scientists. Presently, a large number of drugs in clinical practice have showed pervasive side effect and multidrug resistance. Sulfonyl or sulfonamide hybrids became one of the most attractive subjects due to their broad spectrum of pharmacological activities. Sulfonyl hybrids were broadly explored for their anticancer activities and it was found that they possess minimum side effect along with multi-drug resistance activity. This review describes the most recent applications of sulfonyl hybrid analogues in anticancer drug discovery and further discusses the mechanistic insights, structure-activity relationships and molecular docking studies for the potent derivatives.

Rhodium(III)-catalyzed Oxidative Coupling of N-Methoxybenzamides and Ethenesulfonyl fluoride: a C–H Bond Activation Strategy for the Preparation of 2-Aryl ethenesulfonyl fluorides and Sulfonyl fluoride Substituted γ-Lactams

A method for the synthesis of 2-aryl ethenesulfonyl fluorides and sulfonyl fluoride substituted γ-lactams was developed through a rhodium(III)-catalyzed oxidative coupling of N-methoxybenzamides and ethenesulfonyl fluoride (ESF) in moderate to excellent yields. This protocol featured an exclusive E-stereo selectivity and a monoselective ortho activation of sp2 C–H bonds of the phenyl rings. This research revealed that the much less reactive Heck coupling partner ethenesulfonyl fluoride (ESF) possesses the feasibility for coupling with sp2 C–H bonds to provide a class of new sulfonyl fluoride scaffolds for the SuFEx click reaction.

A Rh-Catalyzed Air and Moisture Tolerable Aldehyde (Ketone)-Directed Fluorosulfonylvinylation of Aryl C(sp2)–H Bonds

The first Rh-catalyzed activation of ortho sp2 C-H bonds of aldehydes (ketones) for monoselective coupling with ethenesulfonyl fluoride was accomplished without covalent or transient preinstallation of imines. The 42 examples revealed that the developed method has the advantage of a wide scope and functional-group tolerability. Application of this method for complicated natural product modification was also accomplished.

Recent Developments on Phenstatins as Potent Antimitotic Agents

BACKGROUND Phenstatin and their derivatives display remarkable antiproliferative activity toward a wide variety of preclinical tumor models. Structural simplicity and excellent stability of phenstatins offer a stimulating premise for developing various derivatives with profound antimitotic activity and excellent cytotoxicity. OBJECTIVE To do analysis of literature that phenstatins derivatives inhibit tubulin polymerization through their interaction at the colchicine binding site of microtubules and arrest the G2/M phase of the cell cycle. In addition, phenstatin derivatives are undergoing clinical evaluation as vascular targeting/disrupting agents and also exhibit direct antiangiogenic properties. METHODS An organised well designed and appropriately managed search of bibliographic databases for peer-reviewed research literature using a focused review question and inclusion/ exclusion criteria has been done for this article. CONCLUSION In this review article, the synthesis and structure-activity relationships of phenstatin and a wide number of their reported analogues with modifications to ring A, ring B, and to the keto position are discussed in the perspective of medicinal chemistry with proper conclusion.