Isolation of polyphenol compounds from olive waste and inhibition of their derivatives for <i>α</i>-glucosidase and <i>α</i>-amylase
作者:Zhihong Wang、Sheng Peng、Mijun Peng、Chengzhang Wang
DOI:10.1080/14786419.2018.1538217
日期:2020.8.17
Olive waste was used as a sustainable resource because it contained a variety of valuable compounds. The polyphenols active fraction from enrichment by microporous resin and extraction with ethyl acetate were analysed by different chromatographic methods. A total of 14 polyphenolic compounds were isolated and identified by structure elucidation. Based on the above obtained compounds, tyrosol was selected as a characteristic polyphenol and participated in transesterification reaction to synthesise beta-ketoester using Yb(OTf)(3). Then the Biginelli reaction with benzaldehyde, urea and ketoester (1:1.2:1.2) was performed at 90 degrees C for 3.0 h under the acidic condition. In addition, the beta-ketoester prepared using tyrosol with benzyl had a greater inhibitory effect on alpha-glucosidase and alpha-amylase, and the inhibition of enzyme activity for 3, 4-dihydropyrimidinone derivatives prepared using abovementioned beta-ketoester was improved significantly. Meanwhile, fluorine-containing dihydropyrimidinone derivatives were considerable inhibitors for both enzymes.
Antihypertensive dihydropyridine compositions, optical isomers and
申请人:Syntex (U.S.A.) Inc.
公开号:US04672071A1
公开(公告)日:1987-06-09
Compositions containing dihydropyridine derivatives which are useful for treating congestive heart failure, hypertension, or angina have the formula: ##STR1## or a pharmaceutically acceptable acid addition salt thereof, wherein n is an integer from 0 to 8; Y is --O--, --NH--, --NR.sub.2 --, --S--, --S(O)--, --S(O).sub.2 --, or a bond; R.sub.1 and R.sub.2 are each independently A.sub.1, A.sub.2, A.sub.3 or A.sub.4 where A.sub.1 is --(CH.sub.2).sub.m (CHOH).sub.p CH.sub.2 OH; A.sub.2 is --(CH.sub.2).sub.q CH.sub.(3-r) [(CH.sub.2).sub.s OH].sub.r ; A.sub.3 is --(CH.sub.2).sub.q CH.sub.(3-r) [(CH.sub.2).sub.p COOR.sub.3 ].sub.r ; and A.sub.4 is --(CH.sub.2).sub.m COOR.sub.3 ; where m is an integer from 1 to 8; p is an integer from 0 to 4; q is an integer from 0 to 8; r is 2 or 3; s is an integer from 1 to 4; and R.sub.3 is H or alkyl of 1 to 18 carbon atoms; R.sub.4 is --NO.sub.2, --CF.sub.3, or halo; and R.sub.5 is lower alkyl or --CH.sub.2 CH.sub.2 OCH.sub.3. Also disclosed are optical isomers of the above compounds, as well as intermediates in the preparation of these final products.