6,7-二氢-6-甲基-3-甲硫基吡喃[4,3-c]吡唑-4-(2H)-酮衍生物的合成及生物活性

6-甲基-5,6-二氢吡喃-2,4-二酮和二硫化碳、碘甲烷缩合得到5,6-二氢吡喃-2,4-二酮的二硫缩醛化合物,然后和取代肼反应得到1位取代和2位取代6,7-二氢-6-甲基-3-甲硫基吡喃[4,3-c]吡唑-4-(2H)-酮衍生物。其化学结构通过单晶X衍射、1HNMR、13CNMR、元素分析证实。生物活性测试结果初步表明,该类化合物表现出一定的杀菌和对前列腺癌细胞PC3的抑制活性。     

Hydrothermal synthesis of flaky crystallized La2Ti2O7 for producing hydrogen from photocatalytic water splitting

Flaky monoclinic La₂Ti₂O₇ was prepared via a hydrothermal method based on the reaction of Ti(SO₄)₂ and La(NO₃)₃. Relative to the solid-state reaction sample, the flaky La₂Ti₂O₇ showed higher surface areas, much smaller crystal size and more efficient light absorption. All these factors led to the higher photoactivity to produce H₂ from water splitting under UV irradiation.     

Nanocomposite route to the stabilization of porous ϑ-alumina

Stabilization of -alumina phase by silica was studied in nanocomposite (diphasic) alumina-silica gels by XRD and BET surface areas measurements. Five wt.% of silica (22 nm particles) increased the crystallization temperature of to -alumina by about 100°C from boehmite (10 nm particles) derived alumina. Stabilization of -alumina was caused by the formation of intimate contact (Al-O-Si) between components by diffusion of silica into the defect alumina structure.Also with the Department of Agronomy.     

Allelopathic Effects of Volatile Monoterpenoids Produced by <Emphasis Type="Italic">Salvia leucophylla</Emphasis>: Inhibition of Cell Proliferation and DNA Synthesis in the Root Apical Meristem of <Emphasis Type="Italic">Brassica campestris</Emphasis> Seedlings

Salvia leucophylla, a shrub observed in coastal south California, produces several volatile monoterpenoids (camphor, 1,8-cineole, -pinene, -pinene, and camphene) that potentially act as allelochemicals. The effects of these were examined using Brassica campestris as the test plant. Camphor, 1,8-cineole, and -pinene inhibited germination of B. campestris seeds at high concentrations, whereas -pinene and camphene did not. Root growth was inhibited by all five monoterpenoids in a dose-dependent manner, but hypocotyl growth was largely unaffected. The monoterpenoids did not alter the sizes of matured cells in either hypocotyls or roots, indicating that cell expansion is relatively insensitive to these compounds. They did not decrease the mitotic index in the shoot apical region, but specifically lowered mitotic index in the root apical meristem. Moreover, morphological and biochemical analyses on the incorporation of 5-bromo-2-deoxyuridine into DNA demonstrated that the monoterpenoids inhibit both cell-nuclear and organelle DNA synthesis in the root apical meristem. These results suggest that the monoterpenoids produced by S. leucophylla could interfere with the growth of other plants in its vicinity through inhibition of cell proliferation in the root apical meristem.     

Prediction of DNA-binding regulatory proteins in bacteriophage T7

The high-resolution structure of several specific DNA-bindingproteins have been determined, and they display a common structuralmotif which mediates their binding to DNA. This motif consistsof two -helices connected by a sharp turn, and its amino acidsequence has several distinguishing features. A computer searchof the proteins coded by the genome of bacteriophage T7 hasbeen performed in an attempt to identify those proteins thatpotentially contain this motif. Eight proteins were found tohave regions similar to that of the motif. Of these, three arerelatively small, have no known function and are good candidatesfor being DNA-binding regulatory proteins. The methods describeduse commonly available computer programs and databases, andare therefore easy to implement.     

过氧化氢在生成戊二酰-7-氨基头孢烷酸过程中的影响

头孢菌素C(CPC)在D-氨基酸氧化酶为催化剂的情况下,与O2反应生成α-ketoadipyl-7-ACA,再与过氧化氢反应生成戊二酰基-7-氨基头孢烷酸(Gl-7-ACA).在此反应中生成的α-ketoadipyl-7-ACA是造成目标产物收率低的关键因素之一.通过加入适量的双氧水可以使剩余的α-ketoadipl-7-ACA转化为Gl-7-ACA,从而使裂解的收率提高5%.     

Laboratory and field tests with the synthetic sex pheromone of threeMatsucoccus 1 pine bast scales

Matsunone, (2E,4E)-4.6,10,12-tetramethyl-2,4-tridecadien-7-one, is the primary sex pheromone ofMatsucoccus resinosae, M. thunbergianae, andM. matsumurae. The synthetic compound was tested in the laboratory and in field tests with all three species, and significantly more males responded to synthetic matsuone than to controls. The attraction of synthetic matsuone to males in field tests was not significantly different from that of virgin females at the same matsuone release rate. An analog of matsuone previously shown to be biologically active was also tested in the laboratory withM. resinosae andM. thunbergianae, and field tested withM. resinosae. The active analog required a dose approximately 100 times greater than matsuone to yield maximum laboratory bioassay response, and in field tests, attraction was not significantly different from controls at doses at which matsuone was significantly attractive.Homoptera: Coccoidea: Margarodidae.Deceased.     

乌苏里江流域TRMM降水数据精度评价与修正

将地面站点观测的降水数据作为基准降水数据,评估汛期热带降雨观测计划(TRMM)降水产品3B42研究型数据(V7)与实时降水数据(RT)的日以及月尺度数据在黑龙江省乌苏里江流域的时空精度。结果表明:在时间尺度上,TRMM 3B42V7与3B42RT的日降水数据与站点降水数据相比,均系统性偏小,且相关性不是很好;相对而言,3B42RT与站点数据的偏差程度较小,相关性较好;月尺度数据与日尺度数据相比,月数据精度均有很大提高,且2种产品数据精度相差不大;在空间尺度上,TRMM 3B42V7和3B42RT都能较好地展现乌苏里江流域降水的空间分布特征。针对评估结果,使用加法和乘法模型对TRMM 3B42V7和3B42RT的月降水数据进行修正。修正后,2种TRMM卫星降水产品的月降水数据精度均有提高,并且加法模型修正效果更好。因此,可选取加法模型修正后的3B42RT月尺度降水数据用于汛期乌苏里江流域的相关水文研究。     

Simple and economic syntheses of some (Z)-7- and (Z)-9-alkenyl acetates,and of (E,Z)-7,9-dodecadien-1-yl acetate,the sex pheromone of the European grapevine moth,using aleuritic acid as a common starting material

Short syntheses of (Z)-7-dodecen-1-yl acetate, (Z)-7-tetradecen-1-yl acetate, (Z)-9-dodecen-1-yl acetate, and (Z)-9-tetradecen-1-yl acetate from 7-hydroxyheptanal and 9-oxononanoic acid precursors obtained by oxidative cleavage of easily available aleuritic acid are reported. The key step in these syntheses is a stereoselective Wittig reaction between aldehyde and alkyl-phosphonium salt. Wittig-Horner type reaction of 7-hydroxyheptanal and diethyl cyanomethylphosphonate gave the ,-unsaturated nitrile derivative which after protection of the hydroxyl group was reduced to the corresponding aldehyde. Wittig reaction of the latter, followed by acetylation, completed the synthesis of (E,Z)-7,9-dodecadien-1-yl acetate, the sex pheromone of the European grapevine mothLobesia botrana Schiff.     

地老虎性信息素类似物E－7－十五碳烯－1－醇乙酸酯的合成

以紫胶桐酸为原料，经三步反应合成了地老虎性信息素类似物Ｅ－７－十五碳稀－１－醇乙酸酯。关键步骤是１６－羟基－９Ｅ－十六碳烯酸（２）在ＤＢＵ作用下的脱羧反应。