Phthalide classification

As already mentioned [(3), (10), (13), 79, 82, 83] many other types of electron impact induced reactions exist which do not belong to the classification used in this chapter. Among these are reactions which proceed via cyclic reactive intermediates or cyclization processes accompanied by hydrogen transfer at one step of the reaction sequence. This last-mentioned decomposition shall be discussed briefly. Compounds of structure 108 yield intense fragments at m/e 133,110116. 2H labelling of the carboxyl function does not shift the signal mje 133, and it was argued by the authors that the reaction possibly proceeds via the phthalide, 109 (21). 

PLANT Sources, chemical structures and classifications of natural phthalides Chemical Structure of Phthalide... 

The basic core structure of phthalide is l(3H)-isobenzofuranone, which contains a benzene ring (ring A) fused with a y-lactone (ring B) between carbon atoms 1 and 3 (Fig. (1)). To date, all known natural phthalide compounds have been identified as derivatives of l(3H)-isobenzofiiranone. The structures of these derivatives either have the core structure substituted with one or more groups at different positions or contain a reduced form with one, two or no double bond(s) in ring A and various substitutions at different positions. The detailed structures of the naturally occurring phthalide derivatives identified from plants are discussed in the Classifications of Natural Phthalides Section below. 

The details of the classifications and chemical structures of four types of natural phthalides are illustrated in Figs. (2-6). Most of the isolated natural phthalides belong to the 3-substituted phthalide type, which accounts for about 61% of the total known naturally occurring phthalides, and of these, non-alkaloid phthalides constitute the most important subtype due not only to their abundance in nature (75 compounds identified) but also their extensively reported pharmacological activities. The pharmacological activities of individual phthalides are discussed in the following Biological Activity Section. 

CAS 77-09-8 EINECS/ELINCS 201-004-7 Synonyms 3,3-Bis (4-hydroxyphenyl)-1(3H)-isobenzofuranone 3,3-Bis (4-hydroxyphenyl) phthalide 3,3-Bis (p-hydroxyphenyl) phthalide o-Di (p-hydroxyphenyl) phthalide Dihydroxyphthalophenone 1(3H)-lsobenzofuranone, 3,3-bis (4-hydroxyphenyl)- Phthalide, 3,3-bis (p-hydroxyphenyl)-Classification Dye Empirical C20H14O4... 

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