A series of novel 2-(1-substituted-1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines (4) were synthesized and their structure was characterized by ^1H NMR, ^13C NMR and elemental analysis. Their solubility in both polar and non-polar solvents is significantly improved owing to the introduction of ethyl or methylthio group at cyclododecyl ring as compared with parent compounds [1, 2-(1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines]. However, their fungicidal activity against Rhizoctonia solani is less than that of parent compounds. X-ray diffraction analysis of a representative compound (4d) showed that the conformation of 12-membered ring is still [3333], in which the ethyl group present at the side-exo position and the thiadiazoline ring at the comer carbon. The thiadiazoline plane is perpendicular to the cyclododecyl one.
Shu Hui Jin Xiao Mei Liang Xu Yang Fu Heng Chen Dao Quan Wang
An efficient synthesis ofα-D-GlcpNAc-(1→2)-[α-D-ManpNAc-(1→3)-]α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-L-Rhap(1), the repeating unit of the O10 antigen from Acinetobacter baumannii was achieved via sequential assembly of the building blocks,p- methoxylphenyl 2,4-di-O-benzoyl-α-L-rhamnopyranoside(2);2-O-allyloxycarbonyl-3,4-di-O-bcnzoyl-α-L-rhamnopyranosyl tri- chloroacetimidate(3);4-methoxylphenyl 3-O-allyloxycarbonyl-4-O-benzoyl-α-L-rhanmopyranoside(4);2-azido-3-O-benzoyl-2- deoxy-4,6-O-isopropylidene-α-D-mannopyranosyl trichloroacetirnidatc(5);2-azido-3,4,6-tri-O-benzoyl-2-deoxy-α,β-D-glucopyr- ano syl trichloroacetimidatc(6).The total yield of 1 from 4 was 4.7%.
Jian Jun ZhangGuang Hui ZongXiao Mei LiangYun Qi LiDao Quan WangFan Zuo Kong
Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates(1)in total yields of 45 and 57%,respectively.
Chuan Jin Hou Xiao Mei Liang Jing Ping Wu Dao Quan Wang
Six novel 12-alkoxycarbonylmethylene-1,15-pentadecanolides (3) were synthesized from 2-nitrocyclo-dodecanone by the Michael addition with acrolein followed by ring enlargement, Nef reaction and Wittig-Homer reaction. Their structures were confirmed bv 1H NMR, IR and elemental analysis. The preliminary bioassay showed that they have some fungicidal activity.
Jian Jun Li Shu Hui Jin Xiao Mei Liang De Kai Yuan Dao Quan Wang
Six new 4"-benzyloxyimino-4"-deoxyavermectin B la derivatives were synthesized from avermectin Bla by the selective protection of C-5-hydroxy group, oxidation of C-4"-hydroxy group, and deprotection followed by reaction with O-substituted hydroxylamine hydrochlorides. Their structures were confirmed by IR, 1H NMR, 13C NMR and MS. Insecticidal activities of the derivatives against Phopalosiphum pseudobrassicae, Spodoptera exigua and Pluteua xylosteua were evaluated.
Yue Mei JiaXiao Mei LiangXue Qin.FangJing Ping WuDao Quan WangChang Hui RuiXian Lin FanHai Yan ZhaoYun Xia Wang