Strana 1 od 127 výsledky
Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2),
Sixty-three amide alkaloids, including three new, piperflaviflorine A (1), piperflaviflorine B (2), and sarmentamide D (4), and two previously synthesized ones, (1E,3S)-1-cinnamoyl-3- hydroxypyrrolidine (3) and N-[7'-(4'-methoxyphenyl)ethyl]-2-methoxybenzamide (5), were isolated from the aerial
The objective of this study was to determine the chemical profile and to evaluate the antibacterial activity of the essential oils of Piper species and modulation of the antibiotic activity, using the microdilution method to determine the minimum inhibitory concentration. The chemical components
Bioactivity-guided fractionation of a CH2Cl2 extract from the leaves of Piper aduncum afforded three new dihydrochalcones, piperaduncins A [3], B [4], and C [5], as well as two known dihydrochalcones, 2',6'-dihydroxy-4'-methoxydihydrochalcone [1] and 2',6',4-trihydroxy-4'-methoxydihydrochalcone [2]
Fifteen known compounds including four triterpenoids (1-4), one sterol (5), one diketopiperazine alkaloid (6) and nine phenolics (7-15) were isolated from the stems of Piper wallichii. Their structures were elucidated by means of spectroscopic analysis, and acidic hydrolysis in case of the
Various parts of Piper obliquum Ruíz & Pavon yielded the new alkenylphenols obliquol A (1) and obliquol B (2), the new 4-chromanone 3 together with the known compounds 4 and 5. A synthesis of obliquol B (2) was developed in order to confirm its structure and to provide sufficient amounts for
Piper nigrum finds an extensive application in antibacterial preparations belonging to Ayurvedic system of medicine. A bioguided extraction and fractionation of the petroleum ether extract of the berries of P. nigrum afforded 2E, 4E, 8Z-N-isobutyleicosatrienamide (1), pellitorine (2), trachyone (3),
Piper betle L. (Piperaceae) leaves which are traditionally used in India and China in the prevention of oral malodor was examined by bioassay-guided fractionation to yield allylpyrocatechol (APC) as the major active principle which showed promising activity against obligate oral anaerobes
Fractionation of the petroleum ether extract from the leaves of Piper gibbilimbum collected in Papua New Guinea afforded four new alkenylphenols, gibbilimbols A-D (1-4). The structures of the isolates were elucidated by spectroscopic methods, mainly 1D- and 2D-NMR spectroscopy. Gibbilimbols A-D were
Phenolic compounds are widely distributed in Nature and act as pharmacologically active constituents in many herbal medicines. They have multiple biological properties, most notably antioxidant, antibacterial and cytotoxic activities. In the present study an attempt to correlate the phenolic
The petroleum ether and chloroform extracts of the root of Piper chaba showed antimicrobial, antileishmanial and cytotoxic activities. Further bioactivity-guided fractionation led to the isolation of Bornyl piperate (1), piperlonguminine (2) and piperine (3). This is the first report of isolation of
Piper cubeba L. is the berry of a shrub that is indigenous to Java, Southern Borneo, Sumatra, and other islands in the Indian Ocean. The plant is usually used in folk traditional medicine and is an important ingredient in cooking. The purpose of this study was to isolate and purify the
Several natural piper amides and their mimics were synthesized by developing a new strategy of amide formation. The piper amides were tested against both gram +ve and gram -ve bacterial strains and found that they are particularly more active against Staphylococcus aureus and Chromobacterium
Piperaceae is a family of tropical plants known to have antifungal, antibacterial, tumour-inhibitory, antiviral, antioxidant, molluscicidal and leishmanicidal activities. In this work, extracts and fractions from aerial parts of Piper abutiloides (Piperaceae), a traditional medicinal plant, were
Gibbilimbols A [(E)-4-(4-decenyl)phenol, 1], B [(E)-4-(3-decenyl)phenol, 2], C [(E)-4-(4-octenyl)phenol, 3] and D [(E)-4-(3-octenyl)phenol, 4] were synthesized by coupling the phenolic parts with the alkyne parts and then reducing the triple bond of the resulting alkynylphenols. These alkenylphenols