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Adhatoda beddomei and Adhatoda vasica leaf, known as ‘Vasaka ’ and/or ‘Vasa ’ in Ayurveda and ‘Malabar nut’ in English, is an official drug in the Indian Pharmacopoeia . The medicinal properties of these plants are due to the presence of pyrroquinazoline alkaloids. An UHPLC–ESI/MS/MS method in both positive and negative electrospray ionization in multiple‐reaction‐monitoring mode was developed and validated for the estimation of alkaloids and flavonoids in Adhatoda species and their marketed herbal formulations. Chromatographic separation was achieved on an Acquity UPLC® BEH C18‐column using a gradient elution with 0.1% formic acid in water and methanol. The developed method was validated as per International Conference on Harmonization guidelines and found to be accurate with overall recovery in the range 94.2–105.0% (RSD ≤ 1.71%), precise (RSD ≤ 3.44%) and linear (R 2 ≥ 0.9992) over the concentration range of 0.5–1000 ng/mL. The total content of alkaloids and flavonoids were highest in the chloroform and aqueous fraction of A. vasica leaf, respectively. The results indicated that the developed method was simple, rapid, sensitive, selective and accurate for the estimation of multiple bioactive constituents in crude mixture, and therefore could make a contribution to the quality control of Adhatoda species and its derived herbal formulations.  相似文献   
2.
A facile and scalable methodology for the preparation of optically active (3S)‐1‐benzylpyrrolidin‐3‐ol ( 3 ), an important drug precursor, is reported. Starting from the naturally occurring alkaloid (?)‐vasicine ( 1 ), a major alkaloid of the plant Adhatoda vasica, 3 was obtained in 84% overall yield (Scheme 3).  相似文献   
3.
A series of novel halogen-substituted deoxyvasicinone {2,3-dihydro-7-halopyrrolo-[(2,1-b)]-quinazolin-9-(1H)-one and 2,3-dihydro-5,7-dihalopyrrolo-[(2,1-b)]-quinazolin-9-(1H)-one} derivatives was synthesized by condensation of halogenated anthranilic acids (2, 3, 4, 5) with 4-aminobutyric acid (6) in refluxing m-xylene over phosphorus pentoxide for 3 h to give the desired compounds (7a7d).  相似文献   
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