Pyrole-2-carboxylic acid

R. S. Bradley and A. D. Care. J. Chem. Soc. 1953, 1688-90. Vapor pressure AH sublimation, 2-thenoic, 2-furoic, and pyrolle-2-carboxylic acids, 40-50°C. 

The Nicolaus group has isolated several pyrole carboxylic acids and indole derivatives from degradation studies of melanins [11, 56-58]. Among these degradation products are the following pyrole carboxylic acids ... 

Binns and Swan [59] have also isolated similar pyrole carboxylic acids after the oxidative degradation of melanins. 

A. Joll, T. Huynh and A. Heitz, Off line tetramethylammonium hydroxide thermochemolysis of model compound aliphatic and aromatic carboxylic acids decarboxylation of some ortho and/ or para substituted aromatic carboxylic acids, J. Anal. Appl. Pyrol., 70, 151 167 (2003). 

Previous analysis of Uinta Basin bitumens (6,10) have shown that the predominant nitrogen types are pyrollic, amide, and aromatic nitrogen. Predominant sulfur types are sulfide, sulfoxide, and thiophenic sulfur predominant oxygen types are ketones, phenols, carboxylic acids, and possibly appreciable concentrations of furans. The aromatic (basic) nitrogen is expected to participate in irreversible adsorption on acidcracking catalysts (13) and it could require an increased cat-to-oil ratio. Previous analyses (10) have indicated also that Uinta Basin bitumen is high in naphthenic hydrocarbon and low in free paraffins. This is illustrated by the results given in Table II in which over 60% of the saturates... 

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