Improved Diazo-Transfer Reaction for DNA-Encoded Chemistry and Its Potential Application for Macrocyclic DEL-Libraries

DNA-encoded libraries (DEL) are increasingly being used to identify new starting points for medicinal chemistry in drug discovery. Herein, we discuss the development of methods that allow the conversion of both primary amines and anilines, attached to DNA, to their corresponding azides in excellent yields. The scope of these diazo-transfer reactions was investigated, and a proof-of-concept has been devised to allow for the synthesis of macrocycles on DNA.

Unusual Cleavage of N-N Bond of 1-Arylamino-1,2,3-triazole Derivatives: A Simple and Alternate Approach to 4,5-Disubstituted-1H-1,2,3-triazoles

In this communication, the authors described the synthesis of 1-arylamino-1,2,3-triazole derivatives via diazo transfer reaction on active methylene hydrazones. Further, we have observed the reduction of 1-arylamino-1,2,3-triazole using Pd/C, H2 to result in unusual N-N bond cleavage to give 4,5-disubstituted-1H-1,2,3-triazole.

A ‘sulfonyl-azide-free’ (SAFE) aqueous-phase diazo transfer reaction for parallel and diversity-oriented synthesis

Diazo transfer reactions are notoriously associated with the use of potentially explosive sulfonyl azides. Handling of the latter can be avoided with the use of this new protocol.