Triazole: A Promising Antitubercular Agent

Abstract

Tuberculosis is a contagious disease with comparatively high mortality worldwide. The statistics shows that around three million people throughout the world die annually from tuberculosis and there are around eight million new cases each year, of which developing countries showed major share. Therefore, the discovery and development of effective antituberculosis drugs with novel mechanism of action have become an insistent task for infectious diseases research programs. The literature reveals that, heterocyclic moieties have drawn attention of the chemists, pharmacologists, microbiologists, and other researchers owing to its indomitable biological potential as anti-infective agents. Among heterocyclic compounds, triazole (1,2,3-triazole/1,2,4-triazole) nucleus is one of the most important and well-known heterocycles, which is a common and integral feature of a variety of natural products and medicinal agents. Triazole core is considered as a privileged structure in medicinal chemistry and is widely used as 'parental' compounds to synthesize molecules with medical benefits, especially with infection-related activities. In the present review, we have collated published reports on this versatile core to provide an insight so that its complete therapeutic potential can be utilized for the treatment of tuberculosis. This review also explores triazole as a potential targeted core moiety against tuberculosis and various research ongoing worldwide. It is hoped that this review will be helpful for new thoughts in the quest for rational designs of more active and less toxic triazole-based antituberculosis drugs.

Ruthenium-Catalyzed Azide Alkyne Cycloaddition Reaction: Scope, Mechanism, and Applications

“…Heating to 60-80 °C did provide a more rapid reaction for Cp*RuCl(PPh 3 ) 2 , but ambient temperature could be applied by running the reaction for longer time at higher catalyst loading.…”

“…Fig. 1 shows some of the products formed using either Cp*RuCl(PPh 3 ) 2 or Cp*RuCl(COD) as the catalyst. Figure 1.…”

“…It is worth noting that for internal alkynes, both Tüzün 58 and Hou 59 showed a higher energy transition state for the C-N bond forming step than observed initially for small substrates and terminal alkynes. 2 were the most active. 62 In addition to mass spectrometry, X-ray diffraction and NMR spectroscopy, the authors have also used DFT calculations to elucidate the mechanism of the reaction.…”

“…Table 1 provides a summary of catalysts for RuAAC, together with selected references to their application, while the remainder of this section deals with more specialized Ru-catalysts as well as Ru-catalysts that afford the 1,4-disubstitued 1,2,3-triazole isomer. 2 and Cp*RuCl(COD). Nolan and co-workers investigated the effect of using 16-electron ruthenium complexes of the general structure Cp*RuLX in RuAAC,…”

“…106 The polymer-bound ruthenium(III) catalyst 47 (Scheme 23) was prepared by reaction of RuCl 3 with a polystyrene-tethered -alanine ligand, affording a supported catalyst An interesting ruthenium-catalyzed tandem reaction has been described by Bhattacharjee and co-workers. 108 In the presence of silver, the ruthenium compound [Ru(dppp) 2 Table 2. …”