Diamide derivatives containing a trifluoromethylpyridine skeleton: Design,synthesis, and insecticidal activity

Diamide derivatives are biologically active molecules that have been widely applied in recent years in research on pesticides, especially insecticides.  Using a simple and environmentally friendly scheme, a series of new diamide derivatives containing a trifluoromethylpyridine skeleton was designed, synthesized, and confirmed by ¹H, ¹⁹F and ¹³C NMR, and HR-MS.  Their insecticidal activities against Plutella xylostella and Helicoverpa armigera were measured and the relationship between structure and activity was investigated.  Eight of the title compounds (D2, D5, D10, D21, D28, D29, D30 and D33) showed 100% activity against P. xylostella at 500 mg L^–1.  One compound, D33, still showed 100% activity against P. xylostella at 100 mg L^–1 and had the lowest LC₅₀ (lethal concentration 50%, 3.7 mg L^–1) among the synthesized compounds.  Molecular docking analysis revealed that D33 could be thoroughly embedded in the active pocket of the ryanodine receptor via hydrogen bonding in a manner similar to the commercial insecticide chlorantraniliprole.     

偶氮苯衍生物的光致变色性及其应用

综述了一些偶氮苯衍生物(ABD)的结构类型、变色特性、变色机理以及在光色材料科学领域如液晶聚合物、自组装单分子膜、非线性光学材料等方面的研究进展及存在的困难。     

pH值对盐酸小檗碱烷基化衍生物表观油水分配系数的影响

目的：探讨pH值和结构修饰对盐酸小檗碱及其烷基化衍生物表观油水分配系数（P）的影响。方法：建立紫外分光光度法测定盐酸小檗碱及其烷基化衍生物含量的检测方法,并采用摇瓶法测定盐酸小檗碱及其烷基化衍生物在正辛醇-缓冲液体系中的表观油水分配系数。结果：pH值在2.0-8.0时,小檗碱lgP值均小于0,且其在水中的lgP值最小。小檗碱衍生物lgP值均大于0,但变化不大;随着修饰碳链的延伸,其油水分配系数逐渐增大,8-十六烷基小檗碱lgP值在不同pH值条件下均大于1,推测其在胃肠道的吸收优于小檗碱。结论：37℃下,pH值对盐酸小檗及其碱衍生物的表观油水分配系数影响不大,但与其结构改造中引入基团的极性呈正相关。     

中国荷斯坦成年公牛可消化有机物进食量与尿嘌呤衍生物排出量的关系分析

尿液嘌呤衍生物法作为一种估测瘤胃微生物蛋白质合成量的新方法,克服了原有方法的缺点,简单易行,通过欧洲牛羊的实验证明该方法与其它方法的测定结果有很好的一致性,但此方法亦有其不足。由于尿中嘌呤衍生物排出量受动物品种的影响很大,不同品种间无通用性,所以现有的研究成果不能用于中国品种牛,更难以使该方法应用于生产。而国内在此方面的报道很有限,所以急需建立各品种反刍动物的估测模型,扩大该方法的应用范围。试验采用3头月龄(22±0.2),体重为(641±26.889)kg,体况相近的中国荷斯坦成年公牛,设计3×3的拉丁方,通过调整日粮精粗比来考察可消化有机物进食量对中国荷斯坦成年公牛尿嘌呤衍生物(PD)排出的影响。结果发现,试验牛尿中嘌呤衍生物中尿囊素大约为73%￣88%,黄嘌呤和次黄嘌呤的含量很小,可以忽略不计,与以往对成年反刍动物的研究结果相似,与同个体犊牛期的研究结果相反。PD的排出量随可消化有机物(DOMI)和可消化粗蛋白(DCP)进食量升高而上升,存在较强的相关性(R2=0.88,n=9),其排出水平为414.09￣975.59mmol/d。肌酐酸的排出较稳定,各处理间差异不显著(P>0.05)。PDC与DOM和DCP进食量存在正相关,这与以往成年反刍动物的研究结果是相似的,与同个体犊牛期的研究结果相反,但相关性较弱。     

6,7-亚甲二氧基硫代苯并二氢吡喃-4-酮衍生物的合成及抑菌活性

以亚甲二氧基苯为起始原料,经过溴化、硫化、环化等反应合成了19个未见文献报道的6,7-亚甲二氧基硫代苯并二氢吡喃-4-酮衍生物,其结构均经核磁共振氢谱和质谱确认。初步抑菌活性测试结果表明,在50 mg/L下,目标化合物对供试7种植物病原菌均有不同程度的抑制作用,其中化合物5b、5i、5k和5l对马铃薯干腐病菌 Fusarium solani的抑制率均达75%以上,5h和5i对番茄灰霉病菌Botrytis cinerea的抑制率分别是67.7%和70.4%。     

The Effect of Substituent,Degree of Acetylation and Positioning of the Cationic Charge on the Antibacterial Activity of Quaternary Chitosan Derivatives

A series of water-soluble cationic chitosan derivatives were prepared by chemoselective functionalization at the amino group of five different parent chitosans having varying degrees of acetylation and molecular weight. The quaternary moieties were introduced at different alkyl spacer lengths from the polymer backbone (C-0, C-2 and C-6) with the aid of 3,6-di-O-tert-butyldimethylsilyl protection of the chitosan backbone, thus allowing full (100%) substitution of the free amino groups. All of the derivatives were characterized using ¹H-NMR, ¹H-¹H COSY and FT-IR spectroscopy, while molecular weight was determined by GPC. Antibacterial activity was investigated against Gram positive S. aureus and Gram negative E. coli. The relationship between structure and activity/toxicity was defined, considering the effect of the cationic group’s structure and its distance from the polymer backbone, as well as the degree of acetylation within a molecular weight range of 7–23 kDa for the final compounds. The N,N,N-trimethyl chitosan with 100% quaternization showed the highest antibacterial activity with moderate cytotoxicity, while increasing the spacer length reduced the activity. Trimethylammoniumyl quaternary ammonium moieties contributed more to activity than 1-pyridiniumyl moieties. In general, no trend in the antibacterial activity of the compounds with increasing molecular weight or degree of acetylation up to 34% was observed.     

Rapid determination of glucose,fructose and sucrose in potato tubers by capillary gas chromatography

Summary A method has been developed for the rapid quantification of glucose, fructose and sucrose in potato tubers by capillary gas chromatography. Baseline separation of trimethylsilyl derivatives of β-D(−) fructose, α-D(+) glucose β-D(+) glucose, myoinositol (internal standard) and sucrose was achieved in under 10 min with a detection range of 10 ng to 3 μg per component. Use of an on-column injector resulted in the retention of a proportion of injected sucrose by the column, despite an oven starting temperature of 140°C. This did not occur with a splitless injection system (inlet temperature 220°C).     

The comparative study digestion and metabolism of nitrogen and purine derivatives in male, Thai, Swamp buffalo and Thai, Brahman cattle

Studies on in vivo digestion, rates of passages, metabolism of nitrogen, urinary purine derivative excretion and blood metabolites were carried out in Thai Brahman cattle and Thai swamp buffaloes (16 months old). The animals were fed mixed diets based on pineapple (Ananas comusus) waste silage containing urea‐N (NPN) and true protein from a concentrate (TP). The Brahman cattle (310 ± 15 kg) were heavier than the swamp buffaloes (195 ± 9.4 kg) and had higher dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) intakes when compared on the basis of their metabolic body weight (BW^0.75), but these intakes did not differ significantly when the diets of each animal species were compared. The total tract, apparent digestibilities of dry matter (DM) and organic matter (OM) were not significantly different between the animal species when comparing the two types of diets. The NDF digestibility was significantly (P < 0.01) decreased in both animal species when fed the TP diet, but was significantly (P < 0.01) greater in cattle than in swamp buffaloes. The passage rate digesta k₁ (P < 0.01) and the passage rate digesta k₂ (through the caecum and proximal colon) (P < 0.03) were significantly slower, and the total mean retention time (TMRT) (P < 0.01) was significantly longer in swamp buffaloes when compared to Brahman cattle, but the transit time (TT) showed no difference (P = 0.07) between the animal species or the diets. The N intakes were not different in both animal species and diets, but urine‐N was greater (P < 0.05) in Brahman cattle than that in swamp buffaloes. Urine N and digestibility of N were significantly (P < 0.04) higher in animals fed the NPN diet than those fed the TP diet. Urinary purine derivatives (PD) and the creatinine (Cr) excretion of swamp buffaloes were significantly (P < 0.01) lower than those in Brahman cattle. Plasma urea‐N (BUN) concentration was significantly (P < 0.01) higher in swamp buffaloes than that in Brahman cattle, but plasma glucose and insulin concentrations were significantly (P < 0.01) higher in Brahman cattle than in swamp buffaloes. The concentrations of non‐esterified fatty acids (NEFA) were not significantly (P > 0.05) different in animals fed different diets. The present study demonstrated that Brahman cattle were better in fiber digestibility than swamp buffaloes at utilizing pineapple waste silage with both N sources.     

New phenolic esters from the resinous exudate of Haplopappus taeda

Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.     

Preparation and sizing mechanisms of neutral rosin size II: functions of rosin derivatives on sizing efficiency

Four rosin derivatives, including rosin esters and rosinamides, were synthesized and used to prepare neutral rosin sizes. Their effects during sizing are discussed in detail. Compared to natural rosin, the rosin derivatives had nearly no effect on sizing even at high retention levels in paper. However, the rosin derivatives in the rosin sizes improved the stability of the emulsion size particles, and there was good correlation between the sizing effect and the stability of the emulsion sizes under neutral to alkaline conditions. On the other hand, the structure of the rosin derivatives significantly influenced the stability and sizing effect of the neutral rosin sizes. In particular, for glycerin rosin ester-rosin sizes, the emulsion stability and sizing effect increased with an increasing proportion of dirosinate, among the glycerin rosin esters. Consequently, it was suggested that the rosin derivatives hardly contribute to the sizing performance of paper but predominantly function to stabilize the neutral rosin size particles, thereby improving the efficiency of the size under neutral to alkaline sizing conditions. Also it was supposed that glycerol dirosinate in the neutral rosin size would probably enable formation of a more stable particle structure to prevent the destructive action of the OH^– ion.This research was presented in part at the 48th annual meeting of the Japan Wood Research Society, Shizuoka, April 1998