Aims: The study is aimed to obtain acylated derivatives of polyprenols which were isolated from leaves of grape Vitis vinifera L.Study Design: Modification of natural compounds.Place and Duration of Study: Department of Organic Chemistry, Institute of the Chemistry of Plant Substances (ICPS). The study was carried out between January, 2011 and December, 2012.Methodology: Polyprenols were acylated by anhydrides of mono- and dicarboxylic acids in absolute benzene in the presence of catalytic amounts of dry pyridine within 1-2 hours (method A). Polyprenols were acylated also by anhydrides of mono- and dicarboxylic acids in the presence of catalyst (dry pyridine) in absence of solvents at 70-80~(D?)D? within 1 or 2 hours (method B). For the acylation of polyprenols the microwave method has been used in absence of the solvent and the catalyst (method C). The courses of reactions were controlled by TLC, HPLC, and HPTLC. Structure of acyl-products determined by IR-, 1H NMR and mass-spectra.Results: In the method A with decreasing of acid’s strength and increasing of molecular weight the yield of acyl-products is decreased. Acylation by benzoyl anhydride yielded to acyl-products between acylation by acetic and propionic anhydrides. Decreasing of yields of acyl-products was observed at usage of anhydrides of dicarboxylic acids. In the method B decreasing of the yields was observed also with decreasing of acid’s strength and increasing of molecular weight of the acylating agent. Thus yields were a bit high (in addition 1-6 %). In the method C (MWA) duration of acylation reaction has sharply contracted (on 20 60 times in comparison with the method A, and 10-30 times in comparison with the method B), i.e. yields of acyl-products are enlarged by 13.5-24.6 % (in comparison with a method A) and 7.5-21.6 % (with a method B) at usage of anhydrides of monocarboxylic acids. At MWA acylation by anhydrides of dicarboxylic acids duration of reaction contracts at 20-40 times in comparison with the method A and 10-30 times in comparison with the method B. The yields are increased on 8.2 - 17.5 % (in comparison with the method A) and 5.2-16.5 % (in comparison with the method B).Conclusion: Acylation reactions of polyprenols with anhydrides of mono- and dicarboxylic acids, organic acids have been studied in various conditions. Usage MWA allows performing esterifications with high yields (from 59 % to 89.6 % in the case of monocarboxylic acids and from 56.2 to 78 % in the case of dicarboxylic acids). Duration of MWA acylation reaction was 6-10 minutes in the case of polyprenol acylation by monocarboxylic acids, and 12-14 minutes in the case of dicarboxylic acids. Therefore MWA method, undoubtedly, is a cost effective method for the acylation.
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机译：目的：本研究旨在获得从葡萄葡萄叶中分离的聚戊二烯酰化衍生物。研究设计：天然化合物的修饰研究地点和持续时间：植物化学研究所有机化学系（ ICPS）。该研究在2011年1月至2012年12月之间进行。方法：在催化量的干燥吡啶存在下，在1-2小时内，用单羧酸和二羧酸的酸酐在无水苯中酰化聚戊二烯（方法A）。在没有溶剂的情况下，在催化剂（无水吡啶）存在下，在70-80℃（D 2）D 2的存在下，一元和二元羧酸的酸酐也可将一元和二元羧酸的酸酐酰化。在1或2个小时内（方法B）。为了酰化聚异戊二烯，在没有溶剂和催化剂的情况下使用了微波法（方法C）。反应过程由TLC，HPLC和HPTLC控制。结果表明：在方法A中，随着酸强度的降低和分子量的增加，酰基产物的收率降低，酰基产物的结构由IR，1 H NMR和质谱确定。通过苯甲酸酐的酰化产生在通过乙酸酐和丙酸酐的酰化之间的酰基产物。在使用二羧酸的酸酐时，观察到酰基产物的产率降低。在方法B中，随着酸强度的降低和酰化剂分子量的增加，产率也降低了。因此产率有点高（另外1-6％）。在方法C中，酰化反应的持续时间急剧缩短（与方法A相比缩短了20 60倍，与方法B相比增加了10-30倍），即酰基产物的收率提高了13.5-倍。使用一元羧酸的酸酐时为24.6％（与方法A相比）和7.5％至21.6％（与方法B相比）。在通过二羧酸酐进行MWA酰化时，反应收缩的持续时间与方法A相比为20-40倍，与方法B相比为10-30倍。收率提高8.2-17.5％（与方法相比） A）和5.2-16.5％（与方法B相比）。结论：已在各种条件下研究了聚戊二烯与一元和二元羧酸，有机酸的酸酐的酰化反应。用途MWA可以高收率进行酯化反应（一元羧酸为59％至89.6％，二元羧酸为56.2％至78％）。 MWA酰化反应的持续时间在单羧酸的聚戊二烯酰化的情况下为6-10分钟，在二羧酸的情况下为12-14分钟。因此，MWA方法无疑是一种经济有效的酰化方法。
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