Cinchomeronic anhydrides

Cinchomeronic anhydride and 1,4-dimethojsybenzene react in a melt of aluminium chloride and sodium chloride to give the benzo[g]isoquinoline-5,10-dione (100). An... 

Cinchomeronic anhydride, prepared by refluxing the acid with acetic anhydride for 30 min., taken up in benzene, dry NH3 bubbled into the refluxing and stirred soln., cooled, hot water added, the aq. phase removed, and saturated with SOa at 25 to precipitate the acid amide —> 4-cinchomeronic acid amide. Y 80%. (G. B. Bachman and R. S. Barker, J. Org. Chem. 14, 97 (1949).)... 

The first use of an oxazole as an azadiene in a Diels-Alder cycloaddition was reported by Kondrat eva in 1957. In these seminal studies a variety of alkyl-substituted oxazoles 1 (Ri, R2, R3 = H, alkyl) reacted with maleic anhydride in either benzene or ether to provide the cinchomeronic anhydrides 2, rather than the expected bicyclic ethers analogous to the Diels-Alder adducts of furans (Fig. 3.1). 

Cinchomeronic anhydride yielded a mixture of analogous 4-(2-benzothiazolyl)-pyridine-3- and 3-(2-benzothiazolyl)pyridine4-carboxylic acids. 

Derivatives of some pyridine-dicarboxylic acids are of interest and value. Quinolinic acid anhydride gives, with ammonia, 2-aminocarbonylnicotinic acidi , which in the Hofinann reaction yields 2-aminonicotinic acid. Similarly, cinchomeronic anhydride gives 4-aminocarbonylnicotinic acid and thence 4-aminonicotinic acid . Use of quinolinic imide in the Hofinann reaction produces mainly 3-aminopicolinic acid and cinchomeronic imide gives 3-amino-isonicotinic acid whilst diamides of... 

Paralleling the reaction with ammonia, reactions of cinchomeronic anhydride with alcohols give 4-alkoxycarbonylnicotinic acids almost exclusively This reaction, and those above involving ammonia, can be understood as the attacks of nucleophiles upon the more electrophilic of two carbonyl groups. 

The Pd-catalyzed amination reaction of meso-hexynyl Zn(II) porphyrin with 4-amino-3-iodopyridine provides meso-(5-azaindolyl)-substituted Zn(II) porphyrin 8, which assembles to form a sUpped cofadal dimer by the coordination of the pyridine moiety to the Zn(II) center (Fig. 6) [22]. The condensation reaction of meso-amino Zn(II) porphyrin with cinchomeronic anhydride affords meso-cinchomeronimide-substituted Zn(II) porphyrin 9, which forms a cycUc trimer and its meso-meso Unked Zn(II) diporphyrins assemble to form a discrete cycUc trimer, tetramer, and pentamer (Fig. 7) [23]. 

A mixture of cinchomeronic acid and acetic anhydride refluxed 1 hr., then a mixture of 80%-hydrazine hydrate and glacial acetic acid added dropwise with stirring at reflux temp., and refluxing continued 3 hrs. -> 1,4-dihydroxypyrido-[3,4-d]pyridazine. Y 95%. I. Matsuura and K. Okui, Chem. Pharm. Bull. 17, 2266 (1969). 

Cinchomeronic add (X-18S) condenses with phenylacetic add in the presence of acetic anhydride and triethylamine to yield l-benzylidene-3-oxo-l,S-dihydro-furo [3,4-c] pyridine (X-188) and a mixture of the isomeric acids (X-186) and (X-187). The lactone (X-188) was converted to the dione (X-189) with sodium methoxide. 

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