Base-free synthesis of 1,3,5-triazines via aerobic oxidation of alcohols and benzamidine over a recyclable OMS-2 catalyst

Synthetic and pharmacological developments in the hybrid s-triazine moiety: A review

This article summarizes the most recent advancements in the synthetic and pharmacological approaches along with the structure activity relationship towards the s-triazine and its derivatives. Much attention has been given to s-triazine core due to its facile synthesis, interesting pharmacology, high reactivity, and binding characteristics towards various enzymes. An array of biological applications has been demonstrated by s-triazines including antimalarial, anti-HIV, anti-viral, antimicrobial, anti-tuberculosis to name a few. In the present investigation s-triazine based molecular structures have been assembled in respect to their synthesis and medicinal properties. Further, the competence of s-triazine has been correlated and compared with the other heterocyclic moieties to substantiates-triazine a privileged scaffold. From the literature it is revealed that nucleophilic substitution at 2, 4, and 6 positions is significant for various biological applications. This article would help in assisting the chemists in designing novel molecular entities with high medicinal value.

Recent biological applications of heterocyclic hybrids containing s-triazine scaffold

s-Triazine possesses an auspicious status in the field of drug discovery and development owing to its presence in many naturally occurring compounds as well as commercially available drugs like enasidenib, gedatolisib, bimiralisib, atrazine, indaziflam, and triaziflam. Easy, cost-effective, and efficient access to its derivatives in addition to their splendid biological activities such as anticancer, anti-inflammatory, antiviral, anticonvulsant, anti-tubercular, antidiabetic, antimicrobial, makes it an attractive heterocyclic nucleus in the field of medicinal chemistry. Other than the direct access of its derivatives from simple commercially available starting materials like amidine, the s-triazine derivatives have also been obtained starting from an inexpensive commercially available 2,4,6-trichloro-1,3,5-triazine (TCT) commonly known as cyanuric chloride. Owing to the high reactivity and the possibility of sequential substitution of TCT, a variety of biologically active heterocyclic scaffolds have been installed on this nucleus in order to have more potent compounds. These s-triazine-based heterocyclic hybrids have been reported to show enhanced biological activities in recent years. Therefore, it is important to summarize and highlight recent examples of these hybrids which is imperative to attract the attention of the drug development community.

Functionalized Triazines and Tetrazines: Synthesis and Applications

The molecules possessing triazine and tetrazine moieties belong to a special class of heterocyclic compounds. Both triazines and tetrazines are building blocks and have provided a new dimension to the design of biologically important organic molecules. Several of their derivatives with fine-tuned electronic properties have been identified as multifunctional, adaptable, switchable, remarkably antifungal, anticancer, antiviral, antitumor, cardiotonic, anti-HIV, analgesic, anti-protozoal, etc. The objective of this review is to comprehensively describe the recent developments in synthesis, coordination properties, and various applications of triazine and tetrazine molecules. The rich literature demonstrates various synthetic routes for a variety of triazines and tetrazines through microwave-assisted, solid-phase, metal-based, [4+2] cycloaddition, and multicomponent one-pot reactions. Synthetic approaches contain linear, angular, and fused triazine and tetrazine heterocycles through a combinatorial method. Notably, the triazines and tetrazines undergo a variety of organic transformations, including electrophilic addition, coupling, nucleophilic displacement, and intramolecular cyclization. The mechanistic aspects of these heterocycles are discussed in a detailed way. The bioorthogonal application of these polyazines with various strained alkenes and alkynes provides a new prospect for investigations in chemical biology. This review systematically encapsulates the recent developments and challenges in the synthesis and possible potential applications of various triazine and tetrazine systems.

Direct synthesis of triazines from alcohols and amidines using supported Pt nanoparticle catalysts via the acceptorless dehydrogenative methodology

We report a cost-effective, green, and acceptorless dehydrogenative one-pot synthesis of triazines from primary alcohols and amidines using an alumina-supported Pt nanoparticle catalyst (Pt/Al2O3).

Recent advances in sustainable synthesis of N-heterocycles following acceptorless dehydrogenative coupling protocol using alcohols

In this review, we have summarized various aspects of homogeneous and heterogeneously catalyzed recent advancements in the synthesis of heterocycles following the ADC approach.

Atom-efficient synthesis of 2,4,6-trisubstituted 1,3,5-triazines via Fe-catalyzed cyclization of aldehydes with NH4I as the sole nitrogen source

An atom-efficient, straightforward method for the synthesis of 2,4,6-triaryl-1,3,5-triazines via iron-catalyzed cyclization of aldehydes with NH₄I as the sole nitrogen source is demonstrated. This strategy works smoothly under air atmosphere, and affords symmetrical 2,4,6-trisubstituted and unsymmetrical 1,3,5-triazines with yields from 18% to 72%. Compared to other methods, the present protocol provides a straightforward and atom-efficient approach to 2,4,6-trisubstituted 1,3,5-triazines using an inexpensive, easily available ammonium salt as the sole nitrogen source. Research into the preliminary mechanism indicates that N-benzylidenebenzimidamides are involved in this cyclization reaction.

An atom-efficient, straightforward method for the synthesis of 2,4,6-triaryl-1,3,5-triazines via iron-catalyzed cyclization of aldehydes with NH₄I as the sole nitrogen source is demonstrated.

Aerobic oxidative dehydrogenation of N-heterocycles over OMS-2-based nanocomposite catalysts: preparation, characterization and kinetic study

OMS-2-based nanocomposites doped with sodium phosphotungstate were prepared and their remarkably enhanced catalytic activity and recyclability in aerobic oxidative dehydrogenation of N-heterocycles were examined in detail.

Tandem transformations and multicomponent reactions utilizing alcohols following dehydrogenation strategy

In this review, the progress of tandem transformation of nitro, nitrile and azide functionalities is summarised to develop new C–C and C–N bonds as well as multi-component reactions using alcohols.