TWO FORMS OF NITROGUANIDINE¹

Abstract

NITROGUANIDINB 10633. The effects of 36 other inorganic salts, acids and bases have been studied. Salts and oxides of elements of the transition series had various degrees of promoting power. All alkalies accelerated the reaction. Mineral acids had little effect.4. The effect of some substances on the promoting power of ferrous chloride was examined. Large amounts of hydrochloric acid diminished its effectiveness. Sodium nitrate and sodium chloride had very little effect on the acceleration produced by the ferrous chloride, but the latter caused the reaction to proceed slowly beyond the alcohol stage to the hydrocarbon. Sodium nitrite caused a large increase in the induction time and slightly repressed the main part of the reaction.5. Whether a promoter was present or not, and regardless of the nature of the promoter, the first product of the reduction of the aldehydes appeared always to be almost exclusively the corresponding primary alcohol. The formation of hydrocarbon was sometimes observed as a subsequent reaction, but it was always very slow.6. Hypotheses which might account for the mechanism of the promoter effects observed are discussed.

A Novel Nitration Product Formed during the Reaction of Peroxynitrite with 2‘,3‘,5‘-Tri-O-acetyl-7,8-dihydro-8-oxoguanosine: N-Nitro-N‘-[1-(2,3,5-Tri-O-acetyl-β-d-erythro-pentofuranosyl)- 2,4-dioxoimidazolidin-5-ylidene]guanidine

“…An alternative to the radical-based mechanism for the formation of IV involves formation of N- [1-(2,3,5-tri-Oacetyl-β-D-erythro-pentofuranosyl)-2,4-dioxoimidazolidin-5-ylidene]guanidine, 8, with subsequent N-nitration occurring via the nitronium ion, NO 2 + , which has also been suggested as a nitrating species produced during peroxynitrite reactions carried out in the presence of transition metals and superoxide dismutase (50). However, to N-nitrate guanidino compounds, extremely harsh conditions, involving the use of mixtures of concentrated sulfuric and nitric acids, must be employed (51). This fact, together with previous reports on peroxynitrite-mediated tyrosine nitration, led us to favor • NO 2 over NO 2 + as the nitrating species.…”

Nitroguanidines.

“…The above procedures of preparing nitroguanidine have evolved into two practical methods for its production, which have been also the most extensively studied. These methods are the nitration of guanidine sulfate (8,22,73,127) and of guanidine nitrate (4,19,22,30,57,58,59,60,111,122,132). Marqueyrol and Loriette (73) claimed an 84 per cent conversion of dicyandiamide to nitroguanidine without isolation of the intermediate guanidine sulfate.…”

“…As in the case of other compounds which decompose without melting, the decomposition point varies with the rate of heating. Davis, Ashdown, and Couch (22) described methods of preparing two crystalline modifications of nitroguanidine, which they called a-and /3-nitroguanidine. Subsequent investigation (27) of these crystalline forms proved both to belong to the orthorhombic crystal system.…”

A New Class of Xanthine Oxidase Inhibitors Isolated from Guanidinium Salts*

“…Infrared spectra were recorded from KBr pellets with a Perkin Elmer Model 21 infrared spectrophotometer. Elemental analysis was performed by the Galbraith Laboratory of Knoxville, Tenn. Nitroguanidine was synthesized according to Davis et al (1925). Nitrosoguanidine was prepared by reduction of nitroguanidine according to Sabetta et al (1935).…”