Braulio InsuastyRodrigo Abonı́aJairo QuirogaHerbert Meier2026-03-222026-03-22199310.1002/jhet.5570300139https://doi.org/10.1002/jhet.5570300139https://andeanlibrary.org/handle/123456789/53811Citaciones: 15Abstract 1,2‐Diamino‐4‐methylbenzene 1 reacts in the presence of sulphuric acid with 4‐substituted acetophenones 2a‐e yielding 2,4‐diaryl‐2,3‐dihydro‐2,8‐dimethyl‐1 H ‐1,5‐benzodiazepines 3a‐e and as minor component 2,4‐diaryl‐2,3‐dihydro‐2,7‐dimethyl‐1 H ‐1,5‐benzodiazepines 4a‐e . The ratio 3:4 is in the range of 7:3. The structure determination of the regioisomers was performed by NOE measurements.enChemistryStructural isomerMedicinal chemistryStereochemistryarticle