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21.
Synthesis of silicon-containing azole derivatives with magnesium bromide diethyl etherate,and an investigation of their fungicidal activities 总被引:2,自引:0,他引:2
Itoh H Kajino H Tsukiyama T Tobitsuka J Ohta H Takahi Y Tsuda M Takeshiba H 《Bioorganic & medicinal chemistry》2002,10(12):1959-4034
Enhancement of magnesium bromide diethyl etherate in addition reaction of trimethylsilylmethylmagnesium chloride 5 to 2-(1H-1,2,4-triazol-1-yl)acetophenones 6 allowed us to prepare silicon-containing azole derivatives, which were tested for fungicidal activity and phytotoxicity. Among them, 2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol 1a was determined to be the most effective and potential candidate for novel fungicide. 相似文献
22.
Gastrointestinal enzyme production of bioactive peptides from royal jelly protein and their antihypertensive ability in SHR 总被引:1,自引:0,他引:1
Matsui T Yukiyoshi A Doi S Sugimoto H Yamada H Matsumoto K 《The Journal of nutritional biochemistry》2002,13(2):80-86
In order to clarify the potential physiological function of royal jelly (RJ), we report here the gastrointestinal enzyme production of antihypertensive peptides from RJ. Intact RJ and its protein fraction did not retard the action of angiotensin I-converting enzyme (ACE) activity at all. However, development of ACE inhibition power of RJ was newly observed by pepsin hydrolysis (IC(50)=0.358 mg protein/mL), and the subsequent trypsin and chymotrypsin hydrolyses (IC(50)=0.099 mg protein/mL). Single oral administration of this gastrointestinal RJ hydrolysate (1 g/kg dose) in 10-week spontaneously hypertensive rat resulted in a significant reduction of systolic blood pressure of 22.7 plus minus 3.6 mmHg at 2 hr (P<0.05 vs. 0 hr by one-way ANOVA, n=7). Then, the RJ hydrolysate was fractionated with gel permeation chromatography to obtain the di- and tri-peptides (DTP) fraction. As a result of isolation from the DTP fraction by reversed phase-high performance liquid chromatography, eleven ACE inhibitory peptides were isolated from the DTP-RJ hydrolysate. Some of the ACE inhibitors were derived from the RJ-glycoprotein; eight peptides with the IC(50) value of <10 &mgr;M were identified from natural resources for the first time. Consequently, RJ protein was thought to be a good resource of ACE inhibitory peptides produced by the gastrointestinal enzyme hydrolyses. 相似文献
23.
Kenji Kobata Momoyo Kawamura Makiko Toyoshima Yukiyoshi Tamura Susumu Ogawa Tatsuo Watanabe 《Biotechnology letters》1998,20(5):451-454
Various lipases catalyzed the synthesis of capsaicin analogs by amidation of vanillylamine with fatty acid derivatives in a two-phase system. When methyl myristate was employed as an acyl donor, moderate yields, 40-59%, of capsaicin analog (3) were obtained using Novozym 435, Lipase AK or Lipase PS. Several capsaicin analogs having 4-18 carboxyl carbons were also synthesized from the corresponding fatty acid or its methyl or ethyl ester in 2-44% yields. 相似文献
24.
Yukiyoshi Tamura Shigeharu Nakamura Hiroshi Fukui Mamoru Tabata 《Plant cell reports》1984,3(5):180-182
The growth and sweet diterpene glucosides of Stevia plants propagated by stem-tip cultures were compared with those of the control plants propagated by seeds. There was no significant difference between the two groups both in growth and in chemical composition. As for the contents of sweet diterpene glucosides, however, the clonal plants showed significantly smaller variations than the sexually propagated plants; they were almost as homogeneous as the plants propagated by cuttings. These results suggest that the clonal propagation by stem-tip culture is an effective method of obtaining a population of uniform plants for the production of sweet diterpene glucosides. 相似文献
25.
Saburo Tamura Nobutaka Takahashi Takao Yokota Noboru Murofushi Yukiyoshi Ogawa 《Planta》1967,78(2):208-212
Summary The presence of three water-soluble gibberellins was confirmed in immature seeds of morning-glory (Pharbitis nil). The structure of the main component has been elucidated as 2-O--glucosyl-gibberellin A3. It shows marked growth-promoting activity on rice seedlings but is far less active on dwarf maize mutants d
1, d
2 and d
5. 相似文献
26.
Shigeru Nakano Yoichi Kawaguchi Yoshinori Taniguchi Hitoshi Miyasaka Yukiyoshi Shibata Hirokazu Urabe Naotoshi Kuhara 《Ecological Research》1999,14(4):351-360
The important contribution of terrestrial invertebrates to the energy budget of drift-foraging fishes has been well documented in many forested headwater streams. However, relatively little attention has been focused on the behavioral mechanisms behind such intensive exploitation. We tested for the hypothesis that active prey selection by fishes would be an important determinant of terrestrial invertebrates contribution to fish diets in a forested headwater stream in northern Japan. Rainbow trout, Oncorhynchus mykiss, were estimated to consume 57.12 mg m–2 day–1 (dry mass) terrestrial invertebrates, 77% of their total input (73.89 mg m–2 day–1), there being high selectivity for the former from stream drift. Both the falling input and drift of terrestrial invertebrates peaked at around dusk, decreasing dramatically toward midnight. In contrast, both aquatic insect adults and benthic invertebrates showed pronounced nocturnal drift. Because the prey consumption rates of rainbow trout were high at dawn and dusk, decreasing around midnight, the greater contribution of terrestrial invertebrates to trout diet was regarded as being partly influenced by the difference in diel periodicity of availability among prey categories. In addition, selectivity also depended upon differences in individual prey size among aquatic insect adults, and benthic and terrestrial invertebrates, the last category being largest in both the stream drift and the trout diets. We concluded that differences in both the timing of supplies and prey size among the three prey categories were the primary factors behind the selective foraging on terrestrial invertebrates by rainbow trout. 相似文献
27.
Yukiyoshi Shirasaka Masatoshi Ito Haruki Mikawa Tadao Serikawa Junzo Yamada 《Journal of neurochemistry》1992,58(6):2292-2295
Tremor rats begin to exhibit clinical or electrical absence-like seizures after 6 weeks of age, and by 14 weeks of age, all have seizures. Central-type benzodiazepine receptor binding was investigated in tremor rats and control rats, aged 4 weeks and 16 weeks. Significantly lower benzodiazepine receptor density and no differences in affinity were found in the hippocampus of the tremor rats in comparison with that of control rats at both ages. This abnormality is considered to be due to a tremor gene and may be the cause of absence-like seizures in tremor rats. A significantly lower receptor density was found in the cerebellum at 4 weeks of age in the tremor rats than in the control rats. These changes may be related to tremorous movements in the tremor rats. Receptor density was significantly lower in the brainstems of tremor rats and control rats at 16 weeks of age than at 4 weeks of age, and the decrease was more marked in control rats. These facts may reflect a reduced decrease in the response to the dysfunction of gamma-aminobutyric acidergic neurons, or the function of the gamma-aminobutyric acid/benzodiazepine receptor system may be secondarily increased to suppress seizures in 16-week-old tremor rats. 相似文献
28.
A series of 4-substituted-7-(β-d-ribofuranosyl)-pyrrolo[2,3-d]pyrimidines in which the 4-substituents were systematically varied has been syn 相似文献
29.
The biological activities of various gibberellin biosynthesis-relatedsubstances; mevalonic acid, kaurene derivatives, steviol, GA18,GA38, GA23, GA28 and GA3, were examined using the barley endospermtest, with the "paper disc method", which responds to a verysmall amount of gibberellin. Mevalonic acid was inactive. Kaurene was slightly active andits activity levelled off at a relative small dosage. Thoughthe activity of kaurenol after a short period was similar tothat of kaurene after a longer period, the former showed anoptimum curve of activity after a longer period. Kaurenoic acid,steviol and GA18 also showed an optimum activity curve, aftera short period in which the highest activity increased in thesequence given. The activities of GA38, GA23 and GA3 were foundto be high after a very short period, increasing in the sequencegiven and linearly with an increase in dosage although GA28was very slightly active after a longer period. (Received October 26, 1974; ) 相似文献
30.
Yukiyoshi Yamazaki Shin-ichiro Ogawa Kimiyuki Shibuya 《Bioorganic & medicinal chemistry》2009,17(5):1911-1917
Two highly deuterium-labeled compounds, (R)-K-13675-d11 and (R)-K-13675-d7, were prepared for use as internal standards for low-level quantification of plasma drugs by LC/MS/MS. We successfully demonstrated their utility in pharmacokinetic studies for sensitive and precise drug quantification. 相似文献