Research Info

A simple and efficient procedure for the synthesis of 5-methyl-3,30-dioxo-3H,30H-spiro[furan-2,10-isobenzofuran]- 3,30-dione derivatives, proceeding via a condensation reaction between ninhydrin and various 1,3-dicarbonyl compounds followed by oxidative cleavage of the corresponding 3a,8b-dihydroxy-2- methyl-4-oxo-4,8b-dihydro-3aH-indeno[1,2-b]furans is presented. The syntheses were carried out in water at room temperature and proceeded with short reaction times to give the products with high yields. The structural assignments were supported by IR, 1H NMR, 13C NMR, and mass spectrometry data.
2015 Elsevier Ltd. All rights reserved. Spirocyclic lactones and their derivatives are widely found in medicinal and natural product chemistry.1 The structural rigidity imparted by spirofusion, in association with the latent functionality of the lactone, is postulated as the source of medicinal activity.2 Like spirolactones, furan and its derivatives play an important role in organic chemistry, due to their presence in many natural products and pharmaceuticals and as building blocks for the synthesis of complex natural metabolites.3 Furthermore, multi-functionalized furans are versatile synthetic reagents for the synthesis of various heterocyclic compounds.4 The isobenzofuran structure exists in many natural compounds and its derivatives display various biological activities associated with antifungal, antidepressive, antisecretory, and antitumor function as well as having other uses including colorants and perfumes.5a,b In addition, many of its derivatives have been used as synthons for the synthesis of complex molecules.5c,d As an example, 4-phenyl-3H,30H-spiro [furan-2,10-isobenzofuran]-3,30-dione, known as fluorescamine and containing furan and isobenzofuran motifs in its structure (Fig. 1) is not inherently fluorescent but can react with primary aliphatic amines to produce strongly fluorescent products. This compound has been widely used to detect amino acids, peptides,