RESUMEN
The defensive secretions of two blaniulid millipedes, Nopoiulus kochii and Cibiniulus phlepsii, were characterized by GC-FID and GC/MS analyses, which showed the presence of a complex mixture of benzoquinones, hydroquinones, and oleates. Altogether, 13 compounds were identified. The major compound in the secretions of both analyzed species was 2-methyl-1,4-benzoquinone (toluquinone). The second major constituent in the N. kochii secretion was 2-methyl-3,4-(methylenedioxy)phenol, while in that of C. phlepsii, it was 2-methoxy-3-methyl-1,4-benzoquinone. The defensive secretion of N. kochii also showed a high content of hydroquinones (13.5%) in comparison to that of C. phlepsii (0.8%). Hexyl oleate and octyl oleate were detected for the first time in defensive millipede fluids. The chemical composition of the defensive secretions supports the chemotaxonomic position of the family Blaniulidae in the 'quinone' millipede clade.
Asunto(s)
Artrópodos/química , Quinonas/química , Animales , Artrópodos/metabolismo , Benzoquinonas/química , Benzoquinonas/aislamiento & purificación , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hidroquinonas/química , Hidroquinonas/aislamiento & purificación , Masculino , Cloruro de Metileno/química , Ácido Oléico/química , Ácido Oléico/aislamiento & purificación , Quinonas/aislamiento & purificaciónRESUMEN
The chromatographic behavior of seven 16-oximino derivatives of 3beta-hydropxy-5-androstene have been investigated using the normal-phase (NP) HPTLC chromatographic mode of the type silica-non-polar diluent (benzene)-polar modifier (acetonitrile, ethyl acetate, or dioxane). The linear relationship between the retention constants (R(M)) and the logarithm of the organic modifier content in the mobile phase allowed for the calculation of R(M)0 values. The influence of substituent in the molecule on extrapolated retention data is discussed. To better understand the retention mechanism in the separation of androstene compounds, the functional group contributions (tauX) were compared with Hansch substituent constants (pi). An attempt to quantitate the lipophilicity of the investigated compounds using normal phase thin-layer chromatographic R(M)0 value was made. Also, the relative lipophilicity values determined previously by RPC as well as activity were compared with NPC data.
