Synthetic aspects of 1,4- and 1,5-benzodiazepines usingo-phenylenediamine: a study of past quinquennial

Abstract

This paper presents recent evolutions in the synthetic aspects of 1,5- and 1,4-benzodiazepines using o-phenylenediamine as a precursor and provides an up-to-date review of recent findings (2018–2022).

Pioneering Synthetic Strategies of 2-Substituted Benzothiazoles Using 2-Aminothiophenol

“…Despite its versatility, a drawback lies in the extended reaction time, lasting up to 24 h. The possible reaction mechanism of the reaction is illustrated in Scheme 20, in which both the reactants (1 and 2) converted into imine intermediate (3) by cyclo condensation and, further, a cyclized intermediate (4) was obtained. The cyclized intermediate (4) lost a proton and gave an anionic intermediate (5) in the presence of a base which was converted in the desired product (6).…”

“…The methyl group in (4) became oxidized, resulting in the aldehyde compound (5). The final product (6) emerged after eliminating a proton and the CHO group from (5) (Scheme 21).…”

“…These compounds are defined by their unique ring structures, where at least one of the atoms in the ring is an element other than carbon, commonly nitrogen, sulfur, or oxygen [2,3]. This diversity in composition lends heterocycles remarkable chemical and biological properties, making them central to fields such as pharmaceuticals, materials science, and agrochemicals [4][5][6][7].…”

NiFe2O4@SiO2@PrNH2–DPA–CeCl3: a cerium-based magnetic nano dual-acid catalyst with high efficacy and recyclability for domino sequential synthesis of lactam ring-fused 1,5-benzodiazepines

“…[9][10][11][12] The lactam ring also occupies an essential position in heterocyclic species, maintaining the antibacterial activity of certain compounds. [13][14][15][16][17] There are diverse 1,5-benzodiazepines with a lactam structure that exhibit superior clinical pharmacodynamic effects, such as clobazam, 18,19 C1414S, 20,21 nevirapine [22][23][24] and arfendazam, 25,26 which proves that the fusion of a lactam structure is worthy of attempting during the synthesis of 1,5-benzodiazepines to enhance pharmacological activity.…”

Synthesis, Pharmacological Evaluation, and Molecular Modeling of Lappaconitine–1,5-Benzodiazepine Hybrids

“…They act as positive allosteric modulators of the GABA A receptor complex present in neural tissue. Likewise, 3 H -1,5-benzodiazepines have emerged as powerful pharmacophores [ 41 , 42 ]. We designed a modern and convenient synthetic approach to lappaconitine–1,5-benzodiazepine hybrids based on the acid-catalyzed reaction of o -phenylenediamine with in situ-formed lappaconitine alkynyl ketones.…”