An Unprecedented Synthesis of 3,3‐Disubstituted Isochroman‐1,4‐diones Using Nitrones as Oxygen Atom Donors

Talauxins: Hybrid Phenalenone Dimers from Talaromyces stipitatus

Cultivation and extraction of the fungus Talaromyces stipitatus led to the isolation of five new oxyphenalenone-amino acid hybrids, which were named talauxins E, Q, V, L, and I based on the corresponding one-letter amino acid codes, along with their putative biosynthetic precursor, duclauxin. The rapid reaction of duclauxin with amino acids to produce talauxins was demonstrated in vitro and exploited to generate a small library of natural and unnatural talauxins. Talauxin V was shown to undergo spontaneous elimination of methyl acetate to yield the corresponding neoclauxin scaffold. This process was modeled using density functional theory calculations, revealing a dramatic change in conformation resulting from the syn elimination of methyl acetate.

Recent applications of ninhydrin in multicomponent reactions

Ninhydrin (1,2,3-indanetrione hydrate) has a remarkable breadth in different fields, including organic chemistry, biochemistry, analytical chemistry and the forensic sciences. For the past several years, it has been considered an important building block in organic synthesis. Therefore, there is increasing interest in ninhydrin-based multicomponent reactions to rapidly build versatile scaffolds. Most of the works described here are simple reactions with readily available starting materials that result in complex molecular architectures. Some of the synthesized compounds exhibit interesting biological activities and constitute a new hope for anticancer agents. The present review aims to highlight the multicomponent reactions of ninhydrin towards diverse organic molecules during the period from 2014 to 2019.

This article aims to review recent multicomponent reactions of ninhydrin towards diverse organic scaffolds, such as indeno-fused heterocycles, spiro-indeno heterocycles, quinoxalines, propellanes, cage-like compounds, and dispiro heterocycles.