By using urea, guanidine, thiourea and related compounds instead of amidines, one obtains the uracils.
When heated with ammonia it yields guanidine, and on boiling with alcoholic potash it yields potassium carbonate.
When heated for some time with water to 140° C. in a sealed tube, it is transformed into ammonium thiocyanate, a similar result being obtained by heating the base alone for some hours to 160-170° C. On heating alone for some hours to r70-180° C. it is converted into guanidine thiocyanate.
GUANIDINE, CN 3 H 5 or HN: C(NH 2) 2j the amidine of amidocarbonic acid.
Many derivatives of guanidine were obtained by J.
By the action of nitric acid on guanidine in the presence of sulphuric acid, nitroguanidine, HN: C(NH 2) NH NO 2 (a substance possessing acid properties) is obtained; from which, by reduction with zinc dust, amidoguanidine, HN :C(NH 2) NH NH 2, is formed.
By fusing guanidine with urea, dicyandiamidineH 2 N (HN): C NH CO NH 21 is formed.
Aniline combines directly with alkyl iodides to form secondary and tertiary amines; boiled with carbon disulphide it gives sulphocarbanilide (diphenyl thio-urea), CS(NHC 6 H 5) 2, which may be decomposed into phenyl mustard-oil, C 6 H 5 CNS, and triphenyl guanidine, C 6 H 5 N: C(NHC6H5)2.
ADDITIONAL MONITORING OF YOUR DOSE OR CONDITIONS may be needed if you are taking isoniazid, guanidine, or an oral anticoagulant.
The dihydro derivatives are most probably those compounds which are formed in the condensation of acidyl derivatives of acetone, with urea, guanidine, &c. Tetrahydropyrimidines are obtained by the action of amidines on trimethylene bromide: Br(CH 2) 3 Br+C 6 H 5 C (:NH) NH 2 = 2HBr+C 4 H 7 N 2 (C 6 H 5) .
Uracil and its homologues may be obtained in many cases from the hydrouracils by the action of bromine, and subsequent elimination of the elements of hydrobromic acid; or by the condensation of aceto-acetic ester and related substances with urea, thiourea, guanidine, &c. Uracil, C4H402N2, crystallizes in colourless needles, is soluble in hot water and melts with decomposition at 335Ã‚° C. Hydrouracil, C4H602N2, is obtained by the action of bromine and caustic alkalis on succinamide (H.
When heated for some time with water to 140Ã‚° C. in a sealed tube, it is transformed into ammonium thiocyanate, a similar result being obtained by heating the base alone for some hours to 160-170Ã‚° C. On heating alone for some hours to r70-180Ã‚° C. it is converted into guanidine thiocyanate.
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