N-1-Naphthyl-3-oxobutanamide in Heterocyclic Synthesis: A Facile Synthesis of Nicotinamide, Thieno[2,3-b]pyridine, and Bi- or Tricyclic Annulated Pyridine Derivatives Containing Naphthyl Moiety

Microwave assisted the short time clean synthesis of 1,3-diketones as building blocks in heterocyclic synthesis: a facile synthesis and antimicrobial evaluation of new dihydropyridine, 4H-pyrane, dihydropyridazine, pyrimidine and pyrazole derivatives

Abstract

The compounds bearing naphthalene moiety can be used as medical preparations because of their wide spectrum of biological activity and low toxicity. In this study, a new series of azoles or azines were synthesized from the reaction of the key intermediate 1-(1-hydroxynaphthalen-2-yl)-3-phenylpropane-1,3-dione 3 with a variety of electrophilic and nucleophilic reagents under a variety of mild conditions. The chemical structures of these compounds were confirmed by various spectroscopic methods such as (IR, ¹H-NMR, ¹³C-NMR, mass spectra and elemental analyses). The prepared compounds were screened in vitro for their anti-microbial activity against some species of Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeuroginosa). Anti-fungal activities of the compounds were tested against yeast and mycelial fungi,Candida albicans and Aspergillus flavus. The antimicrobial activity of this series was showed either weak or moderate activities.

Graphic abstract

Applications of alkyl orthoesters as valuable substrates in organic transformations, focusing on reaction media

In this review we focus on applications of alkyl orthoesters as valuable and efficient substrates to perform various classes of two-component and multi-component organic reactions. The article has classified them according to two aspects, which are: (i) a focus on the reaction medium (solvent-free conditions, aqueous media, and organic solvents); and (ii) an examination of product structures. Reaction accomplishment under solvent-free conditions is an eco-friendly process with the absence of volatile toxic solvents, which puts it in line with green chemistry goals. Water is an interesting choice in organic transformations due to its inexpensiveness and safety. The authors hope their assessment will help chemists to attain new approaches for utilizing alkyl orthoesters in various organic synthetic methods. The review covers the corresponding literature up to the beginning of 2020.