查询词典 aldehydes

Some new α,β-unsaturated sulfones were prepared by condensation of 4-nitrophenylsulfonylacetates with aromatic aldehydes in cyclohexane/CH_3CH_2OH in the presence of catalytic amounts of piperidine.

不饱和砜是以对硝基苯磺酰基乙酸酯为原料与芳香醛在六氢吡啶醋酸盐催化下发生缩合反应制得的。

Study on the selective hydrogenation of α,β-unsaturated aldehydes is of great importance in potential industrial applications and theoretical aspects.

因此，对氯代硝基苯和α，β-不饱和醛的选择性加氢研究具有重要的理论意义和工业应用前景。

Study on Surface Enhanced Raman Scattering of Piperidine;2. Using piperidine as catalyst and ethanol as solvent, a series of new 2-amino-3-cyano-4-aryl-6-methoxy-1,4,9,10-tetrahydronaphtho[2,1-b]pyran derivatives were synthesized by one-pot reaction of aromatic aldehydes, malononitrile and 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one at room temperature in good yields.

以芳醛、丙二腈和 7 甲氧基 1，2 ，3 ，4 四氢萘 2 酮为原料，在六氢吡啶催化下以乙醇为溶剂，在室温合成了一系列新的 2 氨基 3 氰基 4 芳基 6 甲氧基 1，4，9，10 四氢萘并 [2 ，1 b]吡喃衍生物，反应条件温和，产率较高，并通过IR ，1HNMR和元素分析表征产物的结构，还通过单晶X射线衍射分析确证产物的构

We used the reported chiral ligand QD-4 derived from quinidine to catalyze the reaction of aldehydes and methyl vinyl ketone in the presence of various additives and found that the highest e.

用喹尼叮衍生物QD-4分别催化醛和丁烯酮以及醛和丙烯酸-萘酚酯的不对称Baylis-Hillman反应，通过改变添加剂和优化反应条件，最终分别取得了最高为49％和70％的e.e值。

Importantly, the significant steric and electronic effects of the reductant aldehydes were for the first time disclosed systematically.

在此反应的研究中，首次较为规律性地揭示了还原剂醛的空间位阻效应和电子效应。

Six calix[4]recorcinarenes are synthesized by the reaction of resorcin as substrates with six aromatic aldehydes, respectively.

以间苯二酚为反应底物，分别与六种芳香醛合成了相应的杯[4]间苯二酚芳烃，并通过红外光谱和氢核磁共振谱对这些化合物进行了表征。

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。

Bicepts femoris dry matter are 9240.16 ug nonane 100g-1 and 13227.85 ug nonane 100g-1 respectively at 6 months. Aldehydes are primary compounds in process of Xuanwei ham, in which the tiptop content is 6744.60 ug nonane 100g-1 and 11326.18 ug nonane 100g-1 in M. semimembranosus and M. Bicepts femoris dry matter at 6 months, and then drops.

醛类是每个加工阶段种类最多、含量最丰富的挥发性化合物，在6个月时的总含量达到最高值半膜肌和股二头肌干物质中的含量分别为6744.60 μg壬烷·100g~(-1和11326.18μg壬烷·100g~(-1)，随后含量下降。

In addition, in suspension cells, expression of both GaWRKY1 and CAD1-A genes and biosynthesis of sesquiterpene aldehydes were strongly induced by a fungal elicitor-preparation and methyl-jasmonate .

另外，在亚洲棉悬浮细胞中，GaWRKY1和CAD1-A的转录水平均倍半萜醛类物质的合成均可以被黄萎病菌激发子和MJ诱导。

By the comparison of juice tlavour components with those of wild grape wine,wefound that wild grapes consisted of acetals,esters,alcohols, aldehydes, ketones etc,theyexisted in glycosidically-bound forms.Some wine flavour components had been poten-tially in grape,fermentation helped them showup,many alcohols and esters formedmade wine aroma and flavour richer and more complicated.

对葡萄汁与酒中的香味成分对比发现，野生葡萄中的香味成分由烷、酯、醇、醛、酮等组成，它们可能以结合态存在于汁中；葡萄酒中的许多香味成分已潜在于葡萄原料中，发酵能使它们充分表现，发酵中形成了较多的醇、酯类物质，使酒的风味更浓郁、复杂。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷