Synthesis, characterization and RHFlab initio simulations of 2-amino-1,3,4-thiadiazole and its annulated ring junction pyrimidine derivatives

Michael addition reaction of the 2-amino-1,3,4-thiadiazole to chalcone as biselectrophile - afforded 5,7-diphenyl-6-[1,3-diphenylpropan-1-on-3-yl][l,3,4]thiadiazolo[3,2-[a]pyrimidine [3] instead of 5,7-diphenyl-5H-[l,3,4]thiadiazolo[3,2-a]pyrimidine [5] via further Michael addition at C[5] in pyrimidine moiety. The structure 3 was established through the aspect of ab initio calculations, elemental analysis and spectral data

Antifungal Activity of Securinine against Some Plant Pathogenic Fungi

The alkaloid securinine was assessed against spore germination of some plant pathogenic and saprophytic fungi (Alternaria alternata, Alternaria brassicae, Alternaria brassicicola, Curvularia lunata, Curvularia maculans, Curvularia pallenscens, Colletotrichum musae, Colletotrichum sp., Erysiphe pisi, Helminthosporium echinoclova, Helminthosporium spiciferum, Heterosporium sp.). Spore germinations of all the tested fungi were inhibited. Alternaria brassicicola, C. lunata, C. pallenscens and H. spiciferum were highly sensitive as complete inhibition of spore germination was observed at very low concentrations (200 ppm).

A new hetisine-type alkaloid from the stems and leaves of Aconitum coreanum / 药学学报

<p><b>AIM</b>To study the chemical constituents of the stems and leaves of Aconitum coreanum (Lèvl.) Rapaics.</p><p><b>METHODS</b>The constituents of Aconitum coreanum were isolated by using various kinds of modern chromatographic methods. The new alkaloid was identified on the basis of spectral analysis.</p><p><b>RESULTS</b>Two compounds were isolated and identified as: 13-dehydro-1beta-acetyl-2alpha,6beta-dihydroxyhetisine (I) and Guanfu base G (II).</p><p><b>CONCLUSION</b>Compound I is a new alkaloid.</p>

The metabolic transformation of (-)-securinine / 药学学报

<p><b>AIM</b>To study the in vitro and in vivo metabolism of (-)-securinine.</p><p><b>METHODS</b>The metabolic transformation of (-)-securinine was studied by using phenobarbital-induced rat liver microsomal incubate containing the NADPH-generating system in vitro and the constitution of the system was optimized. A reversed phase HPLC method was established to analyze the parent drug and its metabolites. The major metabolites were isolated and purified by liquid-liquid extraction, preparative TLC and HPLC, and their structures were elucidated as 6-hydroxyl securinine, 6-carbonyl securinine, 5 beta-hydroxyl securinine and 5 alpha-hydroxyl securinine by 1HNMR, 13CNMR and MS spectral analysis. An HPLC method was developed to analyze securinine and its metabolites in biofluids (bile, urine) of rat. The bile, urine and their enzymatic hydrolyzed samples of the rat i.p. administrated with (-)-securinine were determined by using this method.</p><p><b>RESULTS</b>Four main metabolites of (-)-securinine in rat hepatic microsome incubation were obtained and their structures were elucidated. Metabolites from in vitro study were confirmed in biofluids (bile, urine) which were collected from rats given securinine i.p. It was suggested that 6-hydroxyl securinine was excreted in conjugated form as well by analyzing enzymatic hydrolyzed bile.</p><p><b>CONCLUSION</b>The main metabolic pathway of (-)-securinine in vitro and in vivo is basically elucidated.</p>

Study on the chiral separation of securinine by high-performance capillary electrophoresis and its stereoselective metabolism in rat / 药学学报

<p><b>AIM</b>To establish a high-performance capillary electrophoresis (HPCE) chiral separation method for d-securinine and l-securinine, and use this method to investigate the stereoselective metabolism process of d- and l-securinine in Wistar rats.</p><p><b>METHODS</b>The electrophoretic condition and parameters were investigated and the optimized conditions were as following: the electrophoretic medium was 40 mmol.L-1 Tris-H3PO4 buffer (pH adjusted to 6.0 with H3PO4) containing 32 mmol.L-1 HP-beta-CD as chiral selector. Determination was carried out with a UV detector at 254 nm. The separations were performed at 16 degrees C with a positive voltage of 15 kV. Samples were injected into the capillary by pressure for 6 s. The biological samples (urine, bile, plasma and feces) of rats were alkalized and extracted with ethyl acetate.</p><p><b>RESULTS</b>The experimental results showed that the concentration of HP-beta-CD, the concentration of the running buffer and the pH value of the buffer were the main important factors which effected the resolution. d-Securinine and l-securinine were separated at baseline level under the determination conditions. The determination was not interfered by endogenous components and metabolites. After i.p. administration, the rats excreted more d-securinine than l-securinine through bile, urine and feces. The metabolism process in rats was stereoselective.</p><p><b>CONCLUSION</b>This method is simple, reliable and suitable for studying the stereoselective metabolism of securinine in rats.</p>

Balanced anesthesia with nalbuphine hydrochloride in pediatric patients : preliminary study

This study of the clinical use of nalbuphine as a component of a balanced anesthesia technique was undertaken with the purpose of exploring the feasibility and safety of this drug as well as to establish possible guidelines for its use.