4-Methyl-1,2,3,4-tetrahydro-beta-carbolin-3-carboxylic acid ethyl ester → HCID 12795657, compound
Reaction equation
[CH2:1]([O:3][C:4]([CH:6]1[CH:18]([CH3:19])[C:17]2[C:16]3[C:11](=[CH:12][CH:13]=[CH:14][CH:15]=3)[NH:10][C:9]=2[CH2:8][NH:7]1)=[O:5])[CH3:2]>C1(C)C(C)=CC=CC=1>[CH2:1]([O:3][C:4]([C:6]1[N:7]=[CH:8][C:9]2[NH:10][C:11]3[C:16]([C:17]=2[C:18]=1[CH3:19])=[CH:15][CH:14]=[CH:13][CH:12]=3)=[O:5])[CH3:2]Participants
3
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Procedure
10.2 g of 4-methyl-1,2,3,4-tetrahydro-β-carbolin-3-carboxylic acid ethyl ester is dissolved/suspended in 300 ml xylene and the mixture is boiled for 10 minutes in a Dean-Stark apparatus to remove moisture. After cooling to 100°-110° C., 2.1 mole equivalents of sulphur are added and the mixture is boiled under reflux for 5 hours. The progress of the reaction is followed by DC. Subsequently, the xylene is evaporated in vacuo. The remainder is dissolved in chloroform and purified by chromatography (chloroform-ethanol radient) on silica to remove non-reacted sulphur. 4-Methyl-β-carbolin-3-carboxylic acid ethyl ester having a melting point of 235°-239° C. is obtained in a yield of 72%.