Title: Guanidine
CAS Registry Number: 113-00-8
Additional Names: Aminomethanamidine; carbamamidine; carbamidine; aminoformamidine; iminourea
Molecular Formula: CH5N3
Molecular Weight: 59.07
Percent Composition: C 20.33%, H 8.53%, N 71.14%
Line Formula: (NH2)2C=NH
Literature References: Strong organic base existing primarily as guanidinium ion at physiological pH. Found in turnip juice, mushrooms, corn germ, rice hulls, mussels, earthworms. Prepn of nitrate from dicyanodiamide + ammonium nitrate: Smith et al., Ind. Eng. Chem. 23, 1124 (1931); Davis, Org. Synth. coll. vol. I (2nd ed., 1941) p 302; from SO2, CO2, + NH3: Boivin, US 2762843 (1956); from urea: Mackay, US 2590257 (1952 to Am. Cyanamid); Craig, Minor, US 3009949 (1961 to Deere); Shaver, US 3108999 (1963 to Monsanto); from ammonium thiocyanate or thiourea + ammonia: Watt, Makosky, Ind. Eng. Chem. 46, 2599 (1954). Pharmacology as muscle stimulant: A. I. Podlesnaya, Bull. Exp. Biol. Med. 61, 291 (1966). Clinical evaluation with pyridostigmine in Lambert-Eaton myasthenic syndrome: S. J. Oh et al., Muscle Nerve 20, 1146 (1997). Review of mode of action: D. R. Tershak et al., "Guanidine" in Handbook of Experimental Pharmacology Vol. 61, G. V. R. Born et al., Eds. entitled "Chemotherapy of Viral Infections" P. E. Came, L. A. Caliguiri, Eds. (Springer-Verlag, New York, 1982) pp 343-375. Review of structure activity studies: F. Davidoff, N. Engl. J. Med. 289, 141-146 (1973). General reviews: M. Schenck, Pharmazie 3, 5 (1948); G. Schaefer, "Guanidines and Biguanidines" in International Encyclopedia of Pharmacology and Therapeutics 107, M. Erecinska, Ed. (Pergamon, Oxford 1981) pp 165-185.
Properties: Deliquescent, cryst mass, mp ~50°. pKa ~12.5. Absorbs CO2 from air. Very sol in water, alcohol. On heating to 160° it is converted to melamine and NH3. Keep well closed. LD50 i.p. in mice: 350 mg/kg (Podlesnaya).
Melting point: mp ~50°
pKa: pKa ~12.5
Toxicity data: LD50 i.p. in mice: 350 mg/kg (Podlesnaya)
Derivative Type: Hydrochloride
CAS Registry Number: 50-01-1
Molecular Formula: CH5N3.HCl
Molecular Weight: 95.53
Percent Composition: C 12.57%, H 6.33%, N 43.99%, Cl 37.11%
Properties: Cryst powder. Freely sol in water, alcohol. Aq soln is neutral.
Derivative Type: Nitrate
CAS Registry Number: 506-93-4
Molecular Formula: CH5N3.HNO3
Molecular Weight: 122.08
Percent Composition: C 9.84%, H 4.95%, N 45.89%, O 39.32%
Properties: Cryst powder, mp 214°. Soluble in 10 parts water; in alcohol. Aq soln is neutral.
Melting point: mp 214°
Therap-Cat: Cholinergic.
Keywords: Cholinergic. |