By condensation of (S)-N-[2-[1-(chloromethyl)-5-hydroxy-8-methyl-1,2,3,6-tetrahydrobenzo [1,2-b:4,3-b']dipyrrol-3-ylcarbonyl]-1H-indol-5-yl]-6-(diethylamino) benzofuran-2-carboxamide (I) with phenyl isocyanate (II) by means of triethylamine in THF.

The starting products are prepared as follows: The reaction of pyridine-3-carboxylic acid methyl ester (I) with ethanolamine (II) gives the 2-hydroxyethylamide (III), which by reaction with diketene in THF yields the corresponding acetoacetic ester (V). The reaction of (V) with ammonia in THF affords the expected 3-aminocrotonate ester (VI).

CD-832.HCl can be obtained by several different ways: 1) The cyclization of benzaldehyde (IX) with acetoacetate (V) and crotonate (VII) in refluxing isopropanol gives 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(2-cyanoethyl) 5-[2-(3-pyridylcarboxamido)ethyl] diester (X), which by reaction with tetrabutylammonium fluoride in THF/DMF, or with Na2S in dichloromethane/methanol, eliminates vinyl cyanide yielding the dihydropyridine monoester (XI). Finally, this compound is esterified with (XII) by means of acetyl chloride and acetic anhydride in dichloromethan). 2) The cyclization of benzaldehyde (IX) with crotonate (VI) and acetoacetate (VIII) as before also gives dihydropyridine (X). 3) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the corresponding 3-nitrobenzylidene derivative (XIII), which is then cyclized with crotonate (VII) to afford the previously obtained dihydropyridine (X). 4) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the 3-nitrobenzylidene derivative (XIII), which is then cyclized with 3-aminocrotonic acid ester (XIV) in refluxing isopropanol.

CD-832.HCl can be obtained by several different ways: 1) The cyclization of benzaldehyde (IX) with acetoacetate (V) and crotonate (VII) in refluxing isopropanol gives 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(2-cyanoethyl) 5-[2-(3-pyridylcarboxamido)ethyl] diester (X), which by reaction with tetrabutylammonium fluoride in THF/DMF, or with Na2S in dichloromethane/methanol, eliminates vinyl cyanide yielding the dihydropyridine monoester (XI). Finally, this compound is esterified with (XII) by means of acetyl chloride and acetic anhydride in dichloromethan). 2) The cyclization of benzaldehyde (IX) with crotonate (VI) and acetoacetate (VIII) as before also gives dihydropyridine (X). 3) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the corresponding 3-nitrobenzylidene derivative (XIII), which is then cyclized with crotonate (VII) to afford the previously obtained dihydropyridine (X). 4) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the 3-nitrobenzylidene derivative (XIII), which is then cyclized with 3-aminocrotonic acid ester (XIV) in refluxing isopropanol.

The starting products are prepared as follows: The reaction of pyridine-3-carboxylic acid methyl ester (I) with ethanolamine (II) gives the 2-hydroxyethylamide (III), which by reaction with diketene in THF yields the corresponding acetoacetic ester (V). The reaction of (V) with ammonia in THF affords the expected 3-aminocrotonate ester (VI).

CD-832.HCl can be obtained by several different ways: 1) The cyclization of benzaldehyde (IX) with acetoacetate (V) and crotonate (VII) in refluxing isopropanol gives 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(2-cyanoethyl) 5-[2-(3-pyridylcarboxamido)ethyl] diester (X), which by reaction with tetrabutylammonium fluoride in THF/DMF, or with Na2S in dichloromethane/methanol, eliminates vinyl cyanide yielding the dihydropyridine monoester (XI). Finally, this compound is esterified with (XII) by means of acetyl chloride and acetic anhydride in dichloromethan). 2) The cyclization of benzaldehyde (IX) with crotonate (VI) and acetoacetate (VIII) as before also gives dihydropyridine (X). 3) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the corresponding 3-nitrobenzylidene derivative (XIII), which is then cyclized with crotonate (VII) to afford the previously obtained dihydropyridine (X). 4) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the 3-nitrobenzylidene derivative (XIII), which is then cyclized with 3-aminocrotonic acid ester (XIV) in refluxing isopropanol.

The starting products are prepared as follows: The reaction of pyridine-3-carboxylic acid methyl ester (I) with ethanolamine (II) gives the 2-hydroxyethylamide (III), which by reaction with diketene in THF yields the corresponding acetoacetic ester (V). The reaction of (V) with ammonia in THF affords the expected 3-aminocrotonate ester (VI).

CD-832.HCl can be obtained by several different ways: 1) The cyclization of benzaldehyde (IX) with acetoacetate (V) and crotonate (VII) in refluxing isopropanol gives 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(2-cyanoethyl) 5-[2-(3-pyridylcarboxamido)ethyl] diester (X), which by reaction with tetrabutylammonium fluoride in THF/DMF, or with Na2S in dichloromethane/methanol, eliminates vinyl cyanide yielding the dihydropyridine monoester (XI). Finally, this compound is esterified with (XII) by means of acetyl chloride and acetic anhydride in dichloromethan). 2) The cyclization of benzaldehyde (IX) with crotonate (VI) and acetoacetate (VIII) as before also gives dihydropyridine (X). 3) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the corresponding 3-nitrobenzylidene derivative (XIII), which is then cyclized with crotonate (VII) to afford the previously obtained dihydropyridine (X). 4) The reaction of benzaldehyde (IX) with acetoacetate (V) by means of piperidinium acetate in refluxing benzene gives the 3-nitrobenzylidene derivative (XIII), which is then cyclized with 3-aminocrotonic acid ester (XIV) in refluxing isopropanol.