Citric Acid → HCID 10009809, compound

Participants

Reaction Steps

In order to produce the citrate, the more nonpolar diastereoisomer of 2-[3-(4-dimethylamino-4-phenylcyclohexylmethyl)thioureido]-3-(1H-indol-3-yl)propionic acid methyl ester (135 mg, 0.274 mmole) was dissolved in hot ethanol (11 ml) and combined with a solution of citric acid (57.9 mg, 0.3 mmole) in ethanol (1 ml). After 4 h, no precipitate was visible. Ethanol was removed by distillation down to a volume of 2 ml and the mixture was slowly combined with ether (30 ml). The suspension was stirred for 20 h at RT and cooled for 2 h in the refrigerator. The resultant solid was filtered out, washed with cold ether (2×1 ml) and dried. The nonpolar diastereoisomer of 2-[3-(4-dimethylamino-4-phenylcyclohexylmethyl)thioureido]-3-(1H-indol-3-yl)propionic acid methyl ester citrate could be obtained in this manner as a yellow solid (Example 41, m.p. 158-163° C.) in a yield of 165 mg (88%).

Provenance & Evidence