噁唑烷衍生物的合成与结构测定

近期文献报道从麻黄植物中分离出微量的恶唑烷酮衍生物,并证明是抗炎有效成分.本文根据上述资料,从麻黄生物碱出发。合成5种 N-取代的麻黄碱衍生物,8种恶唑烷衍生物.根据元素分析、红外、核磁共振氢谱、质谱,确定了衍生物结构.经醋酸扭体法和热板法药理试验,化合物(8)有镇痛作用.     

Khat,a Cultural Chewing Drug: A Toxicokinetic and Toxicodynamic Summary

Khat (Catha edulis) is a recreational, chewed herbal drug that has been used as a psychostimulant for centuries in East Africa and the Arabian Peninsula, namely in Somalia, Ethiopia, and Yemen. However, the growing worldwide availability of khat has produced widespread concern. The plant comprises a large number of active substances, among which cathinone, cathine, and norephedrine are the main constituents, which can be included in the group of sympathomimetics of natural origin. In fact, these compounds are amphetamine analogues, and, as such, they have amphetamine-like nervous system stimulant effects. Chewing the leaves gives people a sensation of well-being and increases energy, alertness, and self-confidence. The chronic use of khat is, however, associated with severe cardiac, neurological, psychological, and gastrointestinal complications. The psychological dependence and withdrawal symptoms of khat are the reasons for its prolonged use. The aim of this paper is to review current knowledge on the khat plant with toxicokinetic and toxicodynamic perspectives. Namely, this review paper addresses in vitro, in vivo, and human studies. The models used, as well as the concentrations and doses with the respective biological effects, are discussed. Additionally, the main drug interactions involved with khat are described.     

HPLC-UV法同时测定麻黄中5种麻黄生物碱的含量

目的建立同时分离检测麻黄中麻黄碱(Ephedrine)、伪麻黄碱(Pseudoephedrine)、去甲麻黄碱(Norephedrine)、去甲伪麻黄碱(Norpseudoephedrine)和甲基麻黄碱(Methylephedrine)的含量测定方法。方法采用HPLC-UV法,色谱柱:苯基柱(Alltima Phenyl,250mm×4.6 mm,5μm);流动相:0.02 mol/L磷酸二氢钾溶液-乙腈(96∶4);流速:0.6 ml/min;检测波长:210 nm;柱温:25℃。结果 5种生物碱在13.5 min内即可达到完全分离,E在2.000 8～40.016 0μg/ml线性关系良好;PE在1.003 6～20.072 0μg/ml线性关系良好;NME在0.199 2～3.984 0μg/ml线性关系良好;NMP在0.200 0～4.00 0μg/ml线性关系良好;ME在0.200 4～4.008 0μg/ml线性关系良好。各生物碱的平均回收率均在92%～104%(RSD≤5.76%)。结论本方法可操作性强,简便快速,分离效果好,重现性好,可为麻黄及含麻黄的中西药制剂提供有效的检测手段。     

基于UPLC-DAD-TOF/MS结合HPLC-UV法的麻黄“先煎去沫”样品的化学成分分析

目的建立基于UPLC-DAD-TOF/MS结合HPLC-UV法检测麻黄样品化学成分的方法,以明确麻黄"先煎去沫"样品化学成分间的差异。方法 UPLC-DAD-TOF/MS:Waters ACQUITY UPLC?BEH C18(50 mm×2.1 mm,1.7μm)色谱柱,以甲醇-0.1%甲酸水溶液为流动相梯度洗脱,体积流量0.3 m L/min,柱温40℃,正、负离子模式扫描;HPLC-UV:以十八烷基硅烷键合硅胶为填充剂(150 mm×4.6 mm,5μm),以0.1%磷酸水溶液(含0.05%三乙胺)-乙腈溶液(99∶1)为流动相,等度洗脱,体积流量1 m L/min,检测波长为210 nm,柱温30℃。结果上沫中所含成分较少,去沫下液和全煎煮液中化学成分基本一致。同时,三者均可鉴定出去甲基麻黄碱、去甲基伪麻黄碱、麻黄碱、伪麻黄碱和甲基麻黄碱5个生物碱类成分和1个羧酸类成分(4-羟基-7-甲氧基-2-喹啉羧酸)。但上沫中生物碱含量极低,而全煎煮液中3种生物碱的含量略高于去沫下液。结论麻黄"先煎去"沫理论可能与生物碱类成分关系不大,但仍需后期进行更深入的研究验证。     

麻黄生物碱在人源肠Caco-2细胞单层模型的吸收转运研究

目的:研究传统中药麻黄中左旋麻黄碱(l-ephedrine,LEP)、右旋伪麻黄碱(d-pseudoephedrine,DPEP)和右旋去甲伪麻黄碱(d-norpseudoephedrine,DNPE)3个生物碱在人源肠Caco-2细胞单层模型中的吸收特性。方法:利用人源结肠腺癌细胞系Caco-2细胞单层模型测试LEP,DPEP和DNPE从绒毛面(AP端)到基底面(BL端)、BL端到AP端2个方向的转运过程。应用偶联紫外检测器的反相高效液相色谱法对上述3个生物碱进行定量分析,计算转运参数和表观渗透系数(Papp),并与阳性对照药普萘洛尔和阿替洛尔的进行比较。结果:LEP,DPEP和DNPE双向转运的Papp在1.0×10-5cm.s-1数量级,与在Caco-2细胞单层模型上呈良好吸收的普萘洛尔的Papp在一个数量级。3个生物碱在10~200μmol.L-1的转运效率与浓度呈正相关。结论:LEP,DPEP和DNPE可以通过小肠上皮细胞被动吸收进入体内,为吸收良好的化合物。     

麻黄汤中麻黄生物碱在人尿中的排泄研究

目的:研究人体口服中药复方麻黄汤煎液后,麻黄生物碱在人体内的代谢及排泄情况。方法:健康志愿者口服麻黄汤煎液后,收集不同时间的尿液,采用GC-MS法测定麻黄汤煎液以及人体口服麻黄汤煎液后尿液中的各麻黄生物碱的含量。结果:口服麻黄汤煎液中含去甲基伪麻黄碱(Norpseudoephedrine,NMP)4.38 mg,去甲基麻黄碱(Norephedrine,NME)3.24 mg,麻黄碱(Ephedrine,E)97.45 mg,伪麻黄碱(Pseudoephedrine,PE)26.15 mg,甲基麻黄碱(Methylephedrine,ME)6.16 mg。健康志愿者口服麻黄汤24 h后,尿液中NMP,NME,E,PE和ME的平均排泄量分别为5.20,9.46,68.39,23.73和2.35 mg,其平均累积排泄率分别为118.84%,291.96%,70.18%,90.74%和38.10%。结论:E作为麻黄汤煎液的主要活性成分之一,其在服药后(0~24)h各时间段排泄最快,而ME排泄最慢。口服麻黄汤煎液后,除一小部分的ME以原形排泄外,NMP,NME,E和PE则主要以原形代谢,通过肾脏从尿液中排出。