Synthesis and antibacterial activities of pleuromutilin derivatives

Six new pleuromutilin derivatives were designed and synthesized, confirmed by MS, IR and ^1H NMR techniques. And the antibacterial activities were primarily evaluated in vitro. The results indicated that most of the derivatives showed more potent activities against corresponding bacterial strains than that of pleuromutilin. Especially, compounds 4d and 5b had obvious activities against salmonella compared with pleuromutilin.

Synthesis and antibacterial activity of pleuromutilin derivatives with novel C(14) side chain

In order to find novel antibacterial agents with superior antibacterial activity and overcoming multidrug resistance,a series of pleuromutilin derivatives with novel C（14） side chain were synthesized and evaluated for their in vitro antibacterial activities.The results of antibacterial acticities indicated that most of the derivatives showed potent activities against Gram-positive organisms.In particular,compound lOd exhibited the most potent inhibitory activity compared with pleuromutilin and linezoid,emerged as potential molecule for further investigation.

二正丁基锡二2-(2-甲酰基苯氧基)乙酸酯的合成、晶体结构及杀菌活性

在苯溶液中,将2-(2-甲酰基苯氧基)乙酸与二正丁基氧化锡进行脱水反应,获得二正丁基锡二2-(2-甲酰基苯氧基)乙酸酯(1),并经过元素分析、1H NMR和IR及晶体结构测试技术进行了结构表征。结果表明,晶体属于C2/c空间群,晶胞参数:a=3.324 6(7)nm,b=0.484 54(10)nm,c=2.214 7(5)nm,β=131.373(2)°,V=2.677 3(9)nm3,Z=4,F(000)=1 208,Dc=1.467 g/cm3,μ=0.999 mm-1,R1=0.048 8,wR2=0.104 8。结构单元内包含1个独立分子,形成以六配位锡为中心的斜梯形双棱锥构型;分子间的Sn O(0.346 8 nm)配位作用,中心锡原子为八配位,构成以锡为中心的扭曲的六方双锥构型的一维链状桥环化合物。杀菌活性顺序为:化合物1>二丁基氧化锡>2-(2-甲酰基苯氧基)乙酸。

头孢布烯关键中间体7β位侧链的合成及结构表征

通过对相关文献进行总结归纳,介绍了第三代口服头孢菌素类药物头孢布烯的药理作用,并探索出合成其7β位侧链的实验室方法,即以2-(2-氨基噻唑-4-基)乙酸乙酯为原料,经酰化、水解、酯化、缩合、分离等过程制得目标化合物4-(3-甲基-2-丁烯-1-氧酰基)-(Z)-2-(2-苯乙酰氨基噻唑-4-基)-2-丁烯酸,总收率为30%。

新型噁唑烷酮类化合物5-位侧链的结构改造及抗菌活性

目的对嗯唑烷酮类化合物5-位侧链进行结构修饰与改造，并初步评价其体外抗菌活性。方法以间氟苯胺为原料，经9～12步反应合成目标化合物；采用二倍稀释法，测定目标化合物的体外抗菌活性。结果设计、合成了30个新化合物，其中目标化合物18个，其结构经^1H NMR及MS等方法确证，11个化合物显示出不同程度的抗菌活性，化合物7a，9a和11a的活性较好。结论化合物7a，9a和11a值得进一步研究。