A series of 2-Substituted (1,3,4) thiadiazolo quinazolines were synthesized by the cyclocondensation of 3-amino-2-mercapto quinazolin-4(3H)-ones with various one-carbon donors and screened for their CNS activities (analgesic, anti-inflammatory, sedative-hypnotic and anticonvulsant). Compound III showed good CNS depressant activity, and it is comparable with the reference standard diazepam. While all the test compounds offered significant protection against strychnine-induced and hypoxic induced convulsion, compound III exhibited equivalent activity with the standard diazepam at the dose tested, and it was found to be significant when compared to control.

A direct selenation of arenes and heteroarenes at room temperature has been accomplished. This protocol was enabled by a visible‐light‐promoted single‐electron‐transfer (SET) pathway without a directing group. An array of arenes and heteroarenes, such as indoles, pyrroles, and functionalized aryl substrates could go through this selenation with high yields and regioselectivity. The salient feature of this protocol is the SET achieved by irradiating one of two organic molecules thereby avoiding a sensitizer to form a radical ion pair.

A photo-catalytic regio- and stereoselective difunctionalization of aryl terminal alkynes and aryl conjugated dienes is accomplished.

The synthesis of regio- and stereoselective aryl substituted α,β-unsaturated aldehydes and ketones from activated allenes was achieved. This mild and non-metallic oxidation is exclusively driven by benign ambient air and triggered by visible light. The same starting materials under ideal anaerobic conditions led to the 2,3-diphenylselenation adduct with no trace of oxygenated products, demonstrating dissolved oxygen as a chemical switch for two different reaction pathways. The salient feature of this protocol is the single electron transfer (SET) achieved by irradiation of one of two organic molecules thereby avoiding a sensitizer to form a radical ion pair.