几丁化

Nucleophilic opening of the terminalepoxide 57 by a lithium acetylide from 27 in the presence of BF3·EtO furnishedcompound 58, which had the skeleton of target molecule, subsequent conversionsinvolved the introduction of γlactone gave Annonacin.

然后以三氟化硼参与的炔负离子开环氧反应建立分子骨架，得到化合物58。随后经氢化，引入α，β不饱和丁内酯环、去保护等几步反应，就得到Annonacin。

During the manufacturing of the critical intermediate cephalosporin nucleus --7-amino-3-chloro-cephalosporanic acid diphenylmethyl ester hydrochloride salt, first the feasibility of the one-pot synthetic route of open loop, closed loop and ozonization when chlorine is passed over is qualified by experiments. Then the critical factors that will influence this reaction are studied as follows: the mol ratio of triphenyl phosphite and Diphenylmethyl 3-hydroxy-7-phenylacetaminoceph-3-em-4-carboxylate-l-oxide is four to one; the quantity of the stablizer should be at least more than two to one. The temperature of the system must be 25℃ when chlorine is passed over so that the hydrochloride can be precipitated to obtain cephalosporin nucleus of cefaclor--7-amino-3-chloro-cephalosporanic acid diphenylmethyl ester hydrochloride salt.

在制备关键中间体头孢母核7-氨基-3-氯头孢烷酸二苯甲酯盐酸盐时，先通过实验验证把开环、闭环、臭氧化三步在通入氯气时并为一锅煮的合成路线的可行性之外，又研究了影响该反应的几个重要因素：亚磷酸三苯酯与3-羟基-7-头孢烷-5-亚砜-2-甲酸二苯甲酯的摩尔比为4：1；稳定剂2-甲基-2-丁烯的用量至少大于2：1，通入氯化氢气体时体系温度在25℃时盐酸盐则能够顺利析出，获得头孢克洛的头孢母核—7-氨基-3-氯头孢烷酸二苯甲酯盐酸盐。

The auxiliary can be recovered in high yield (81%) only by filtering and recrystallization. Besides, some other aldehydes have been chosen to test the enantioselectivity of N,N\'-dibenzyl tartamide, in comparison with two other allylaborates reagents developed previously by Roush and Brown, respectively. The results show that %e.e. of homoallylic alcohol is superior to that of the former, and approaches the Brown reagent.

产物经S_N2反应得瑞格列萘中间体-甲基烯丙基-2-氯苯基-叠氮甲烷(17)；同时，将筛选出的新型手性配体N-苄基酒石酸二酰胺用于其他几种醛(正丁醛，异戊醛和环己醛)的不对称烯丙基化反应，并与广泛应用的Roush配体(22)和Brown配体(27)相比较，发现其立体选择性优于Roush配体，并接近Brown配体，但明显具有可回收利用的优势。

In this Ph. D. dissertation, reverse microemulsion method was fully used infabricating and modifying polyacrylamide with functional and high-relative moleculeweight. The copolymerization of 2-acrylamide-2-methylpxopanesulfonic acid, fluorescent monomer 4-methoxy-N-(2-N\', N\'-dimethylamino ethyl)naphthalimide alkyl chloride quaternary ammonium salt, fluorescentmonomer 4-(N\'-methyl-1-piperazinylallyl)-N-butyl-naphthalimide chloride quaternaryammonium salt, Cationic monomer dimethylethylammonium bromide and hydrophobical monomer octadecylacrylate with acrylamide and properties of the copolymers werestudied. The interaction between five polymers and Al_2O_3(012) crystal surface have beensimulated by Materials Studio 3.0 program package, binding energies and non-bondinteraction energies and deformation energies have also been acquired.

本文以制备具有较高相对分子质量和功能型PAM为研究目的，将反相微乳液法运用到其制备及改性的有关环节，通过反相微乳液聚合工艺，将几种改性功能单体2-丙烯酰胺基-2-甲基-丙磺酸、荧光单体2-(4-甲氧基-1，8-萘二甲酰亚胺基)-乙基二甲基烯丙基氯化铵、荧光单体4-(N'-甲基-1-哌嗪基)-N-丁基-1，8-萘烯丙氯季铵盐、阳离子单体丙烯酰氧乙基-二甲基-乙基溴化铵和疏水单体丙烯酸十八酯与AM共聚，制备AMPS改性PAM、荧光示踪型PAM、阳离子单体DMB改性PAM和OA改性PAM等四类不同功能单体改性PAM，并研究其应用性能。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。