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Sodium (1.64 g, 71.3 mmol) was dissolved in ethanol until all gas evolution had ceased. Then cyanamide (1.685 g, 40 mmol) was added. The reaction mixture was stirred for 15 min, 2-chlorophenylisothiocyanate (7.21 g, 42.66) was added and the mixture kept at reflux for 6 hr. The reaction was cooled and diluted with methylene chloride. A white solid precipitated which was filtered and dried to give the sodium salt of N-(2-chlorophenyl)-N″-cyanothiourea. ( 8.26 g, 87.5%). MS(ES+) m/e 210,212 [M+H]+b) N-(2-Hydroxy-3-nitrophenyl)-N′-(2-chlorophenyl)-N″-cyanoguanidine To a stirred solution of the sodium salt of N-(2-chlorophenyl)-N′-cyanothiourea (234 mg, 1 mmol) and 2-hydroxy-3-nitro-aniline(156 mg, 1 mmol) in 2 ml dry DMF was added EDC hydrochloride (384 mg, 2 mmol) under Ar and the reaction stirred at rt for 4 d. The reaction mixture was partitioned between EtOAc and 1 N HCl and the organic extracts were washed with water and brine. After drying (Na2SO4) and evaporation of the solvent under reduced pressure, a red oil was isolated. Chromatography (silica gel, 3% acetone/CHCl3) afforded a bright yellow solid.(30 mg, 9%) which was recrystallized from t-butylmethylether to afford the title compound. 1H NMR(400 MHz, CDCl3) δ 10.93 (s, 1H), 8.53 (s, 1H), 7.92 (d, J=7.8 Hz, 1H),7.61 (d, J=7.8 Hz, 2H), 7.38-7-50 (m, 2H), 7.22 (s, 1H), 7.08 (t, 1H); IR(KBr) 2181 cm−1; MS(ES−) m/e 330[M−H]−; mp. 163-164°.

1. customThe reaction mixture was partitioned between EtOAc and 1 N HCl
2. washthe organic extracts were washed with water and brine
3. customAfter drying
4. custom(Na2SO4) and evaporation of the solvent under reduced pressure
5. customa red oil was isolated
6. custom(30 mg, 9%) which was recrystallized from t-butylmethylether