RESUMEN
Alpinia species, used as ornamental plants and flavoring agents, are renowned for their therapeutic properties and their subsequent use in traditional medicines throughout the world. Alpinia zerumbet (Pers.) B.L.Burtt & R.M.Sm. is the most common Alpinia species encountered in Martinique. Several essential oils (EOs) obtained by hydrodistillation of A. zerumbet flowers collected in various locations on the island at different seasons were analysed to evaluate the influence of the collection period and area on the EOs' chemical compositions and to assess their bioactivity. A combination of GC-FID and GC/MS techniques was used to examine the volatile constituents, leading to the identification of a total of 71 components accounting for 97.8 - 99.3% of the respective total GC-FID areas: among them, nineteen compounds were characterized for the first time in A. zerumbet EOs. The antimicrobial activity of these EOs was assessed against eight bacterial, yeast and fungal strains and two multi-resistant strains: some significant bacteriostatic and fungistatic activities of A. zerumbet flower oils were evidenced. Finally, an interesting insecticidal activity of the flower EO was highlighted for the first time against Aedes aegypti.
Asunto(s)
Alpinia/química , Antiinfecciosos/aislamiento & purificación , Insecticidas/aislamiento & purificación , Aceites Volátiles/aislamiento & purificación , Aedes/efectos de los fármacos , Animales , Flores/química , Cromatografía de Gases y Espectrometría de Masas , Martinica , Aceites Volátiles/química , Aceites Volátiles/farmacología , Estaciones del AñoRESUMEN
A short and straightforward synthesis of the antihistaminic drug mequitazine is reported, based on an efficient palladium catalyzed allylic alkylation of 1-aza-bicyclo[2.2.2]oct-2-en-3-ylmethyl acetate using sodium phenothiazinate in mild conditions.
Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/química , Antagonistas de los Receptores Histamínicos H1/síntesis química , Compuestos Organometálicos/química , Paladio/química , Fenotiazinas/síntesis química , Tiazinas/química , Alquilación , Catálisis , Antagonistas de los Receptores Histamínicos H1/química , Estructura Molecular , Fenotiazinas/química , EstereoisomerismoRESUMEN
Preparative RP-LCMS is widely used to purify compounds from crude reaction mixtures in drug discovery today. Method development for preparative Liquid Chromatography-Mass Spectrometry (LCMS) consists of finding the right balance between speed and quality, often leading to the use of fast generic gradients (5-95% organic mobile phase) to purify compounds of various structures and polarity, which can be sometimes detrimental to the purity of the isolated compound. Isocratic elution is the best method to obtain high purity, but it usually requires a long trial and error method development to find the right eluent composition. Therefore it is mostly used to purify large quantities of product using for instance stack injections, but not for routine purification of structurally diverse compounds. Herein, we describe an empirical method that allows "right-first-time" purifications with isocratic elution on preparative RP-LCMS, permitting isolation of compounds in high purity and yield.