Alkyl phenols, alkenyl cyclohexenones and other phytochemical constituents from Lannea rivae (chiov) Sacleux (Anacardiaceae) and their bioactivity
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- 作者：Dorothy A. Okoth ; Hoseah M. Akala ; Jacob D. Johnson…
- 关键词：Lannea rivae ; Alkenyl phenols ; Alkenyl cyclohexenones ; Alkenyl cyclohexenols ; Cytotoxicity ; Antiplasmodial ; Antibacterial ; Antioxidant
- 刊名：Medicinal Chemistry Research
- 出版年：2016
- 出版时间：April 2016
- 年：2016
- 卷：25
- 期：4
- 页码：690-703
- 全文大小：528 KB
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Hoseah M. Akala (2)
Jacob D. Johnson (2)
Neil A. Koorbanally (1)
1. School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa
2. Department of Emerging Infectious Diseases, United States Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, P.O. Box 54, Kisian-Kisumu, Kenya - 刊物主题：Pharmacology/Toxicology; Biochemistry, general; Cell Biology;
- 出版者：Springer US
- ISSN：1554-8120
文摘
Six novel compounds, 3-nonadec-14′-(Z)-enyl phenol (1a); 4,5-dihydroxy-4,2′-epoxy-5-[16′-Z-18′-E-heneicosenyldiene]-cyclohex-2-enone (2), 2,4,5-trihydroxy-2-[16′-Z-heneicosenyl]-cyclohexanone (3); 4S,6R-dihydroxy-6-[12′-Z-heptadecenyl]-cyclohex-2-enone (4a); 4S,6R-dihydroxy-6-[14′-Z-nonadecenyl]-cyclohex-2-enone (4b); and 1,2,4-trihydroxy-4-[16′-Z-heneicosenyl]-cyclohexane (5) were identified from the roots and stems of Lannea rivae in addition to the known cardanols, 3-heptadec-12′-Z-enyl phenol (1b), 3-pentadec-10′-Z-enyl phenol (1c) and 3-pentadecyl phenol (1d), sitosterol (6), sitosterol glucoside (7), taraxerone (8), taraxerol (9), E-lutein (10), myricetin (11), myricetin-3-O-α-rhamnopyranoside (12), myricetin-3-O-β-galactopyranoside (13) and (-)-epicatechin-3-O-gallate (14). The ketones 4a and 4b were isolated as a mixture and were qualitatively separated and identified by GCMS. Myricetin (11) and epicatechin gallate (14) displayed over 90 % DPPH radical-scavenging activity at 50 μg mL−1, while its glycosides (12 and 13) showed percentages of over 70 % in the same assay. The same compounds 11 and 14 showed antibacterial activity similar to erythromycin and vancomycin against Gram-positive bacteria and were also active against Gram-negative bacteria, but not as much as the cefuroxime, ciprofloxacin and nalidixic acid standards. Compounds 1a–d, 4a–b and 5 were all relatively non-toxic, while 2 (the epoxy cyclohex-2-enone) and 3 (the trihydroxy cyclohexanone) showed more toxicity than the others. These two toxic compounds, 2 and 3 also showed antiplasmodial activity with IC50 values between 0.48 and 2.05 μg mL−1. The mixture of dihydroxy cyclohex-2-enones 4a and 4b, which was far less toxic than 2 and 3, also showed promising antiplasmodial activity and may be a possible lead for further investigation as an antiplasmodial drug.