title: Synthesis of steroidal derivatives containing substituted, fused and spiro pyrazolines.
abstract: An efficient and facile synthesis of fused, substituted and spiro pyrazoline steroid derivatives through a cycloaddition reaction of different α,β-unsaturated ketones with hydrazine acetate in acetic acid is reported. Depending on the starting material, the ring closure reaction provided a mixture of two steroidal pyrazoline epimers that were separated and studied by NMR techniques. In one case it was possible to isolate and characterize the hydrazone derivative as the reaction intermediate, which confirms the mechanism proposed in the literature [11,25,26].
authors.affiliation: Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Químicas, Ciudad Universitaria, C.P. 72570 Puebla, Pue., Mexico.
authors.forename: Anabel
authors.initials: A
authors.lastname: Romero-López
authors.affiliation: Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Químicas, Ciudad Universitaria, C.P. 72570 Puebla, Pue., Mexico. Electronic address: maria.montiel@correo.buap.mx.
authors.forename: Sara
authors.initials: S
authors.lastname: Montiel-Smith
authors.affiliation: Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Químicas, Ciudad Universitaria, C.P. 72570 Puebla, Pue., Mexico. Electronic address: maria.meza@correo.buap.mx.
authors.forename: Socorro
authors.initials: S
authors.lastname: Meza-Reyes
authors.affiliation: Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Químicas, Ciudad Universitaria, C.P. 72570 Puebla, Pue., Mexico.
authors.forename: Penélope
authors.initials: P
authors.lastname: Merino-Montiel
authors.affiliation: Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Químicas, Ciudad Universitaria, C.P. 72570 Puebla, Pue., Mexico.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Vega-Baez
mesh_terms: D060326:Chemistry Techniques, Synthetic; D006834:Hydrazines / Q000737:chemistry; D011720:Pyrazoles / Q000737:chemistry*; D013141:Spiro Compounds / Q000737:chemistry*; D013256:Steroids / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D006834:Hydrazines; D011720:Pyrazoles; D013141:Spiro Compounds; D013256:Steroids
keywords: Cycloaddition; Hydrazine acetate; Hydrazone; Pyrazoline; Unsaturated ketones