CINNOLIN

cinnolin, c8h6n2, a compound isomeric with phthalazine, prepared by boiling dihydrocinnolin dissolved in benzene with freshly precipitated mercuric oxide. the solution is filtered and the hydrochloride of the base precipitated by alcoholic hydrochloric acid; the free base is obtained as an oil by adding caustic soda. it may be obtained in white silky needles, melting at 24-25° c. and containing a molecule of ether of crystallization by cooling the oil dissolved in ether. the free base melts at 39° c. it is a strong base, forming stable salts with mineral acids, and is easily soluble in water and in the ordinary organic solvents. it has a taste resembling that of chloral hydrate, and leaves a sharp irritation for some time on the tongue; it is also very poisonous (m. busch and a. rast, _berichte_, 1897, 30, p. 521). cinnolin derivatives are obtained from oxycinnolin carboxylic acid, which is formed by digesting orthophenyl propiolic acid diazo chloride with water. oxycinnolin carboxylic acid on heating gives oxycinnolin, melting at 225°, which with phosphorus pentachloride gives chlorcinnolin. this substance is reduced by iron filings and sulphuric acid to dihydrocinnolin. the relations of these compounds are here shown:-- c-oh c-oh ch ^ ^ ^ ^ ^ ^ ^ / \_c:c·cooh / \ / \\ / \ / \\ / \ / \\ | | | | c·cooh | | ch | | ch | | ---> | | | ---> | | | ---> | | | | |_ | | n | | n | | n \ / n:n·oh \ / \ // \ / \ // \ / \ // v v n v n v n o-phenyl propiolic oxycinnolin oxycinnolin cinnolin acid diazo hydroxide carboxylic acid cino da pistoia (1270-1336), italian poet and jurist, whose full name was guittoncino de' sinibaldi, was born in pistoia, of a noble family. he studied law at bologna under dinus muggelanus (dino de rossonis: d. 1303) and franciscus accursius, and in 1307 is understood to have been assessor of civil causes in his native city. in that year, however, pistoia was disturbed by the guelph and ghibelline feud. the ghibellines, who had for some time been the stronger party, being worsted by the guelphs, cino, a prominent member of the former faction, had to quit his office and the city of his birth. pitecchio, a stronghold on the frontiers of lombardy, was yet in the hands of filippo vergiolesi, chief of the pistoian ghibellines; selvaggia, his daughter, was beloved by cino (who was probably already the husband of margherita degli unghi); and to pitecchio did the lawyer-poet betake himself. it is uncertain how long he remained at the fortress; it is certain, however, that he was not with the vergiolesi at the time of selvaggia's death, which happened three years afterwards (1310), at the monte della sambuca, in the apennines, whither the ghibellines had been compelled to shift their camp. he visited his mistress's grave on his way to rome, after some time spent in travel in france and elsewhere, and to this visit is owing his finest sonnet. at rome cino held office under louis of savoy, sent thither by the ghibelline leader henry of luxemburg, who was crowned emperor of the romans in 1312. in 1313, however, the emperor died, and the ghibellines lost their last hope. cino appears to have thrown up his party, and to have returned to pistoia. thereafter he devoted himself to law and letters. after filling several high judicial offices, a doctor of civil law of bologna in his forty-fourth year, he lectured and taught from the professor's chair at the universities of treviso, siena, florence and perugia in succession; his reputation and success were great, his judicial experience enabling him to travel out of the routine of the schools. in literature he continued in some sort the tradition of dante during the interval dividing that great poet from his successor petrarch. the latter, besides celebrating cino in an obituary sonnet, has coupled him and his selvaggia with dante and beatrice in the fourth _capitolo_ of his _trionfi d' amore_. cino, the master of bartolus, and of joannes andreae the celebrated canonist, was long famed as a jurist. his commentary on the statutes of pistoia, written within two years, is said to have great merit; while that on the code (_lectura cino pistoia super codice_, pavia, 1483; lyons, 1526) is considered by savigny to exhibit more practical intelligence and more originality of thought than are found in any commentary on roman law since the time of accursius. as a poet he also distinguished himself greatly. he was the friend and correspondent of dante's later years, and possibly of his earlier also, and was certainly, with guido cavalcanti and durante da maiano, one of those who replied to the famous sonnet _a ciascun' alma presa e gentil core_ of the _vita nuova_. in the treatise _de vulgari eloquio_ dante refers to him as one of "those who have most sweetly and subtly written poems in modern italian," but his works, printed at rome in 1559, do not altogether justify the praise. strained and rhetorical as many of his outcries are, however, cino is not without moments of true passion and fine natural eloquence. of these qualities the sonnet in memory of selvaggia, _io fui in sull' alto e in sul beato monte_, and the canzone to dante, _avegnache di omaggio piu per tempo_, are interesting examples. the text-book for english readers is d.g. rossetti's _early italian poets_, wherein will be found not only a memoir of cino da pistoia, but also some admirably translated specimens of his verse--the whole wrought into significant connexion with that friendship of cino's which is perhaps the most interesting fact about him. see also ciampi, _vita e poesie di messer cino da pistoia_ (pisa, 1813).