418759-12-3Relevant academic research and scientific papers
The diastereoisomers methyl 5-(S)-[2-(R)/(S)-methoxycarbonyl)-2,3,4,5- tetrahydropyrrol-1-ylcarbonyl]-1-(4-methylphenyl)-4,5-dihydropyrazole-3- carboxylate
Pilati, Tullio,Casalone, Gianluigi
, p. o178-o180 (2007/10/03)
The title diastereoisomers, methyl 5-(S)-[2-(S)-methoxy-carbonyl)- 2,3,4,5-tetrahydropyrrol-1-ylcarbonyl]-1-(4-methyl-phenyl)-4,5-dihydropyrazole- 3-carboxylate and methyl 5-(S)-[2-(R)-methoxycarbonyl)-2,3,4,5-tetrahydropyrrol- 1-ylcarbonyl]-1-(4-methylphenyl)-4,5-dihydropyrazole-3-carboxylate, both C19H23N3O5, have been studied in two crystalline forms. The first form, methyl 5-(S)-[2-(S)-methoxycarbonyl)-2,3,4, 5-tetrahydropyrrol-1-ylcarbonyl]-1-(4-methylphenyl)-4,5-dihydropyrazole-3- carboxylate-methyl 5-(S)-[2-(R)-methoxycarbonyl)-2,3,4,5-tetrahydropyrrol- 1-ylcarbonyl]-1-(4-methylphenyl)-4,5-dihydropyrazole-3-carboxylate(1/1), 2(S),-5(S)-C19H23N3O5·2(R), 5(S)-C19H23N3O5, contains both S,S and S,R isomers, while the second, methyl 5-(S)-[2-(S)-methoxycarbonyl)-2,3,4,5- tetrahydropyrrol-1-ylcarbonyl]-1-(4-methylphenyl)-4,5-dihydropyrazole-3- carboxylate, 2(S),-5(S)-C19H23N3O5, is the pure S,S isomer. The S,S isomers in the two structures show very similar geometries, the maximum difference being about 15° on one torsion angle. The differences between the S,S and S,R isomers, apart from those due to the inversion of one chiral centre, are more remarkable, and are partially due to a possible rotational disorder of the 2-(methoxycarbonyl)tetrahydropyrrole group.
