Synthesis of 2-Mercapto-(2-Oxoindolin-3-Ylidene)Acetonitriles from 3-(4-Chloro-5H-1,2,3-Dithiazol-5-Ylidene)Indolin-2-ones

The Synthesis and Biological Applications of the 1,2,3-Dithiazole Scaffold

The 1,2,3-dithiazole is an underappreciated scaffold in medicinal chemistry despite possessing a wide variety of nascent pharmacological activities. The scaffold has a potential wealth of opportunities within these activities and further afield. The 1,2,3-dithiazole scaffold has already been reported as an antifungal, herbicide, antibacterial, anticancer agent, antiviral, antifibrotic, and is a melanin and Arabidopsis gibberellin 2-oxidase inhibitor. These structure activity relationships are discussed in detail, along with insights and future directions. The review also highlights selected synthetic strategies developed towards the 1,2,3-dithiazole scaffold, how these are integrated to accessibility of chemical space, and to the prism of current and future biological activities.

5-Chloro-6-oxo-6H-xantheno[4,3-d]thiazole-2-carbonitrile

Xanthones and benzothiazoles are important classes of heterocyclic compounds with versatile biological activities. Herein, we describe a straightforward and scalable synthesis of 5-chloro-6-oxo-6H-xantheno[4,3-d]thiazole-2-carbonitrile, a thiazole-fused xanthone, via a six-step approach, using Appel’s salt for the synthesis of the thiazole ring. The thiazole-fused xanthone was fully characterized employing 1H and 13C NMR spectra, using direct and long-range heteronuclear correlation experiments (HMBC and HMQC).

Oxidative Cyclization of 4-(2-Aminophenyl)-4-oxo-2-phenylbutanenitriles into 2-(3-Oxoindolin-2-ylidene)acetonitriles

A facile and highly efficient method for the preparation of 2-(3-oxoindolin-2-ylidene)acetonitriles from 4-(2-aminophenyl)-4-oxo-2-phenylbutanenitriles is described. The featured transformation operates via nucleophilic intramolecular cyclization and involves oxidation of the aniline moiety. Overall, this modification allowed for the improvement of yields and expansion of the reaction scope.