Three steroidal alkaloids from Buxus hildebrandtii (original) (raw)

New Triterpenoidal Alkaloids from Buxus hyrcana

Phytochemical studies on the methanolic extract of the leaves of Buxus hyrcana pojark, collected in Iran, have resulted in the isolation of two new triterpenoidal alkaloids, (+)-2α,16β ,31triacetylbuxiran (1), (+)-2α,16β ,31-triacetyl-9-11-dihydrobuxiran (2). Spectroscopic methods were used to elucidate the structures of these new natural products.

New triterpenoidal alkaloids from Buxus sempervirens

Zeitschrift Fur Naturforschung C, 2002

Buxus sempervirens, (+)-16α, 31-Diacetylbuxadine and (Ð)-N b -Demethylcyclomikuranine Phytochemical studies on the ethanolic extract of the roots of Buxus sempervirens of Turkish origin have resulted in the isolation of two new triterpenoidal alkaloids, (+)-16α, 31diacetylbuxadine (1), (Ð)-N b -demethylcyclomikuranine (2) along with three known natural products, (Ð)-cyclomikuranine (3), (Ð)-cyclobuxophylline-K ( ) and (+)-buxaquamarine (5) isolated for the first time from this species of genus Buxus. The structures of these new natural products were established on the basis of extensive spectroscopic studies. Compound 1 exhibited antibacterial activity against human pathogenic bacteria and weak phytotoxic activity against Lemna minor Linn.

CHEMICAL CONSTITUENTS OF BUXUS SEMPERVZRENS

A new flavonoid glycoside 1 is isolated from the leaves ofBvurssnnpnvirrnr, and its structure is determined on the basis of spectral studies. It is the first flavonoid glycoside to be isolated from the genus BUXUJ. We also report the isolation of methyl syringate from this plant. The isolation and '3C-nmr spectra of buxpsiine and cyclomicrophylline A are also described. Buxus smpewims L. (Bwaceae) is widely distributed in Eurasia. The H 2 0 extracts of the plant find extensive use in the indigenous system of medicine for the treatment of many diseases (1). Previously, we have reported a number of new steroidal alkaloids and two known flavonoids isolated for the first time from the genus Blrxrrr (2-5). In the present paper, we describe the isolation and structure elucidation of a new flavonoid glycoside, galactobuxin {I], along with methyl syringate 121. The isolation and 13C

Alkaloids from the Leaves of Buxus papilosa

Journal of Natural Products, 1986

A new steroidal alkaloid, cycloxobuxoviricine (l), has been isolated from the leaves ofEuxupapihra and its structure determined by spectroscopic methods. Isolation and 13C-nmr spectrum of another alkaloid, buxaminol B (2), not previously reported from the leaves of this plant is also described. 109 2 EXPERIMENTAL GENERAL EXPERIMENTAL PROCEDURES.-M~SS spectra were recorded on a Varian MAT 3 12 double focusing mass spectrometer connected to DEC-PDP 11/34 computer system. The 'H-nmr spectra were recorded in CDCI, on Bruker AM-300 NMR spectrometer at 300 MHz, while the ',C-nmr spectra were recorded at 75 MHz. Chemical shifts are expressed in ppm. Ir spectra were recorded on a Jasco IRA-I infrared spectrometer. The uv spectra were recorded on Shimadzu UV 240 instrument. The optical rotation was determined with a Polartronic D instrument. PLANT MArERIAL.-The leaves of B. papiha were collected from the northern region of Pakistan by the Forest Institute, Peshawar. The plant was identified by Prof. S. Irtifaq Ali, Department of Botany, University of Karachi, and a voucher specimen has been deposited in the Department of Botany, University of Karachi.

CHEMICAL CONSTITUENTS OF BUXUS SEMPERVZRENS novel flavonoid glycoside

New Triterpenoidal Alkaloids from the Leaves of Buxus papillosa

HETEROCYCLES, 1998

We construct a graph complex calculating the integral homology of the bordered mapping class groups. We compute the homology of the bordered mapping class groups of the surfaces S 1,1 , S 1,2 and S 2,1 . Using the circle action on this graph complex, we build a double complex and a spectral sequence converging to the homology of the unbordered mapping class groups. We compute the homology of the punctured mapping class groups associated to the surfaces S 1,1 and S 2,1 . Finally, we use Miller's operad to get the first Kudo-Araki and Browder operations on our graph complex. We also consider an unstable version of the higher Kudo-Araki-Dyer-Lashoff operations.

Immunosuppressive Activity of Buxidin and E -Buxenone from Buxus hyrcana

Chemical Biology & Drug Design, 2010

Buxidin (1) and E-Buxenone (2), steroidal alkaloids from Buxus hyrcana, are found to possess potent immunosuppressive properties. The activity was tested in vitro on oxidative burst, chemotaxis, T-cell proliferation, and cytokine production. Both compounds showed a significant immunomodulatory activity with clear suppressive effect on oxidative burst and chemotaxis in a dose-dependent manner. They also exhibited suppressive effect on the phytohemagglutinin-stimulated T-cell proliferation. The immunomodulatory activity was further confirmed by the suppression of IL-2 and IL-4 production. Furthermore, molecular docking studies were performed to investigate the binding mode of Buxidin (1) and E-Buxenone (2) with IL-2. Despite the structural differences between Buxidin (1) and E-Buxenone (2), docking results revealed that they adopt a similar binding pattern at the active site of the IL-2. A good agreement between practical and theoretic results indicates that the current docking study could provide an alternate tool for the structural optimization of recently identified ligand as more potent IL-2 inhibitors.