Expedient Access to Novel Bis‐tetrazolopiperazines via Ugi‐azide Reactions

Abstract

A one‐pot four‐component synthesis of bis‐tetrazolopiperazines in moderate to high yields is described. The reaction consists of condensation of aldehydes or cyclic ketones with piperazine, trimethylsilyl azide, and isocyanides. High reaction efficiency, short reaction time, mild reaction condition, use of simple experimental procedure, and prompt isolation of the products are some advantages of this protocol.

An Efficient Ugi‐Azide Four‐Component Approach for the Preparation of Novel 1‐(1H‐tetrazol‐5‐yl)‐10‐chloro‐1,2,3,4‐tetrahydropyrazino[1,2‐a] Indoles

“…In continuation of our previous approaches to the synthesis of pyrazino[1,2‐ a ] benzimidazoles , indoloketopiperazines , 2,6‐diketopiperazines , N , N′ ‐disubstituted piperazines , 1‐(1 H ‐tetrazol‐5‐yl)‐1,2,3,4‐tetrahydropyrrolo[1,2‐ a ] pyrazine derivatives , tetazoles , and bis‐tetrazolopiperazines , herein, we disclose our new synthetic method to novel 1‐(1 H ‐tetrazol‐5‐yl)‐10‐chloro‐1,2,3,4‐tetrahydropyrazino[1,2‐ a ] indoles derivatives (Fig. ).…”

Synthesis of Polyheterocyclic Dimers Containing Restricted and Constrained Peptidomimetics via IMCR-Based Domino/Double CuAAC Click Strategy

“…The developed strategy allowed us to synthesize polyheterocyclic dimers containing both restricted and constrained PHPs (Scheme 1c). To our knowledge, the strategy developed to synthesize dimers via a repetitive IMCR employing a bifunctional starting material is well documented [45][46][47][48][49]. The coupling of MCR with other domino processes (MCR-based domino) is undeniably the best strategy to increase their synthetic potential and to generate molecular complexity.…”

Preparation of novel symmetrical bistetrazole‐carbazole derivatives through a one‐pot Ugi‐azide reaction

“…[ 31,32 ] The Ugi‐azide reaction is a development on the U‐4CR, in which the carboxylic acid is replaced by an azide source such as trimethylsilyl azide (TMSN 3 ) or hydrazoic acid (HN 3 ) for accessing novel 1,5‐DS‐1 H ‐T scafffolds. [ 33–36 ] Particularly significant is that with some exceptions, [ 37,38 ] the preparation of bis‐tetrazoles via the Ugi‐azide reaction has rarely been reported previously.…”