N-Hydroxy guanidine

C-Nitroso Compounds, Oximes, N-Hydroxy guanidines and N-Hydroxyureas... 

A 2006 report detailed the three-step synthesis of N-hydroxy guanidines from N-Cbz protected thioureas for the synthesis of A/ -hydroxy-L-arginine (060L4035). 

N sodium hydroxide solution (5 ml) is added to a stirred suspension of S-methyllsothiosemi-carbazide hydroiodide (2.33 g) and hydroxylamine hydrochloride (0.70 g) In water (6 ml) and stirred for 48 hours. The solution is evaporated In vacuo to provide 1 -amino-3-hydroxy-guanidine. One-third of the residue is dissolved in 16 ml of ethanol and 2,6-dichlorobenzalde-hyde (0.6 g) Is added to this solution. The reaction mixture is then stirred for 48 hours. The solution is then evaporated in vacuo and the residue dissolved in ether (30 ml) and in hydrochloric acid (30 ml). The aqueous phase is rendered alkaline with 2 N sodium carbonate solution and extracted with ether. The ether layer is dried with sodium sulfate and evaporated. 

N-( Hydroxy ethyl), N-nitroguanidine Nitrate (See Hydroxyethylguanidine under "H", and TrinitrophenyInitroguanidine (See Nitrophenyl-guanidine under "N )... 

The 111.6 kg resultant precipitates of N"-[4-(chloromethyl)-4,5-dihydro-4-hydroxy-2-thiazolyl]-guanidine hydrochloride are collected, and washed with 50 L of acetone. In 500 ml of water are dissolved 111.6 kg of N"-[4-(chloromethyl)-4,5-dihydro-4-hydroxy-2-thiazolyl]-guanidine hydrochloride and 32.9 kg of thiourea. The solution is stirred for one hour at 50°C. N -[4-[[(Aminoiminomethyl)thio]methyl]-2-thiazolyl]-guanidine dihydrochloride is formed in the reaction mixture, and this reaction mixture containing this compound is directly used for the next process without isolation of the formed compound. 

Compounds 40 react with guanidine, urea, thiourea, methylisothiourea, guanylthiourea by Lewis-acid catalysis (00S1738) and with thiosemicarbazide, semicarbazide (99IZV361) in the presence of triethylamine to form the corresponding 5,6-oligomethylenepyrimidines and 3-hydroxy-2(thio)-carbamoyl-3-polyfluor-o a 1 k y 1 - 3.3 a. 4.5.6.7 - h e x a h y d r o - 2 / /- i n d a z o 1 e s 41, respectively (Scheme 38). The structure of 41 (thio) is confirmed by X-ray analysis. 

The reaction of thioureas with nucleophiles has been only sparsely studied in the past. Guanidines have been prepared by treatment of corresponding thioureas with propylamine in the presence of lead oxide, and thioureas with a hydroxy-group at the / -position of the N-substituent have been cyclized to oxazolines by refluxing in ethanol in the presence of cupric acetate. The latter reaction was shown to proceed via an intermediate copper complex. ... 

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