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Atta-ur-Rahman

Publications and source records attributed to Atta-ur-Rahman.

At least 91 records · Page 5Linked to original sources
PubMed1997

Two new pregnane-type steroidal alkaloids from Sarcococca saligna.

Two new preganae-type steroidal alkaloids, (20S, 2'Z)-20- (N,N-dimethylamino)-3 beta-(2-methyl-2Z-butenamido)-pregn-5-en-4-one and (20S, 2'Z)-20-(N,N-dimethylamino)-3 beta-(2-methyl-2Z-butenamido)- pregna-5,14-dien-4-one, have been isolated from an ethanolic extract of the roots and stems of Sarcococca saligna, in addition to the two known alkaloids, N-formylchonemorphine and vaganine-A, which have been isolated for the first time from this species.

Anti-Infective Agents↗
PubMed1997

Antifungal diterpenoid alkaloids from Delphinium denudatum.

The roots of Delphinium denudatum have yielded a new diterpenoid alkaloid, 8-acetylheterophyllisine (1), in addition to the known alkaloids vilmorrianone (2), panicutine (3), denudatine (4), isotalatizidine (5), and condelphine (6), as well as 3-hydroxy-2-methyl-4H-pyran-4-one (7). Compounds 1, 3, and 7 have not been isolated from this plant previously. The structures of compounds 1, 3, and 7 were determined through spectral and X-ray diffraction analyses. Compounds 1-3 have shown antifungal activity against a number of human pathogenic fungi.

Alkaloids↗
PubMed1997

Microbial transformation of sclareolide.

The microbial transformation of sclareolide (1) by Curvularia lunata afforded five oxidized metabolites identified as 3-ketosclareolide (2), 1 beta-hydroxysclareolide (3), 3 beta-hydroxysclareolide (4), 1 alpha,3 beta-dihydroxysclareolide (5), and 1 beta, 3 beta-dihydroxysclareolide (6). Fermentations of 1 with Aspergillus niger also produced metabolites 2-6. Metabolites 2-5 were obtained by fermention with Gibberella fujikuroii, while fermentation with Fusarium lini afforded metabolites 4 and 5.

Agaricales↗
PubMed1997

New steroidal alkaloids from Buxus longifolia.

Four new steroidal alkaloids, (+)-cyclovirobuxeine F (1), N-benzoyl-O-acetylbuxalongifoline (2), buxasamarine (3), and (+)-cyclobuxamidine (4), along with two known steroidal bases, 16 alpha-acetoxybuxabenzamidienine (5) and trans-cyclosuffrobuxinine (6), were isolated from the leaves of Buxus longifolia. The alkaloids 1-4 showed significant antibacterial activity.

Alkaloids↗
PubMed1996

Plants and AIDS.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Antifungal steroidal lactones from Withania coagulance.

Two new withanolides, 14,15 beta-epoxywithanolide I [(20S,22R) 17 beta, 20 beta-dihydroxy-14 beta,15 beta-epoxy-1-oxo-witha-3,5,24-trienolide] and 17 beta-hydroxywithanolide K (20S,22R) 14 alpha,17 beta,20 beta-trihydroxy-1-oxo-witha-2,5,24-trienolide] have been isolated from the whole plant of Withania coagulance and their structures were elucidated by spectroscopic techniques. The latter compound was found to be active against a number of potentially pathogenic fungi.

Antifungal Agents↗
PubMed1991

Inhibition of platelet activating factor by ajmaline in platelets: in vitro and in vivo studies.

The in vitro and in vivo effects of ajmaline and its derivatives on platelet aggregation and platelet-activating factor (PAF) induced death in rabbits was studied. Ajmalinc and acetyl ajmaline selectively inhibited PAF-induced aggregation in a concentration related manner. Weak or no inhibition of aggregation was observed when ADP, collagen or arachidonic acid were used as aggregating agents. Similarly ajmaline or acetyl ajmaline also inhibited the lethal effects of PAF in the rabbit. PAF (8-11 microg/kg i.v.) caused sudden death in rabbits due to platelet aggregation and cardiac failure. Pretreatment of rabbits with ajmaline (50 mg/kg i.p.) protected conscious rabbits from PAF (11 microg/kg i.v.)-induced death. Since PAF is a powerful inducer of platelet aggregation via stimulation of specific PAF membrane receptors, our data is suggestive that ajmaline (an anti-arrhythmic agent) could emerge as a new class of PAF antagonists.

Journal Article↗
PubMed1991

New bioactive compounds of plant origin.

Crude extracts of Withania somnifera (WS) and Polygonum equisetiforme (PE) as well as the pure compounds isolated therefrom were screened for antibacterial and antifungal activity against 20 bacterial and 17 fungal cultures. The crude extract of PE and WS inhibited the growth of T. mentagrophyte, M. canis and A. boydii at an MIC of 450-500 microg/ml whereas the pure compounds inhibited the growth at MIC of 300-350 micro/ml. Species of Corynebacterium, Bacillus, Streptococcus and Staphylococcus were found to be highly susceptible to both the crude sad the pure compounds. MIC values of both crude extracts for different organisms tested were found to be higher (200-350 microg/ml) than the pure compounds (150-170 microg/ml). The crude extract of PE did not inhibit the growth of Ps. aeruginosa, however, the pure compound was found to be bacteriostatic. Brine shrimp and BALB/c mice lethality test indicated that these extracts maybe toxic at high concentration.

Journal Article↗
PubMed1989

Structure of leuconolam sesquihydrate.

8a-Ethyl-7,8,8a,10,11,12a-hexahydro-12a- hydroxyindolizino[8,1-ef][1]benzazonine-6,13-(5H,9H)-dione sesquihydrate, C19H22N2O3.3/2H2O, Mr = 353.42, triclinic, P1, a = 9.250 (2), b = 13.366 (3), c = 9.217 (2) A, alpha = 97.786 (3), beta = 119.590 (3), gamma = 70.726 (3) degrees, V = 934.8 A3, Z = 2, Dx = 1.255 g cm-3, Mo K alpha,lambda = 0.71073 A, mu = 0.839 cm-1, F(000) = 378, T = 293 K. The final R value is 0.061 for 1646 significant [I greater than 3 sigma(I)] reflections. The alkaloid from the leaves of Rhazia stricta is built up by a benzene ring ortho disubstituted with a 4,5-dihydro-5-hydroxy-2-oxo-pyrrol-1,4,5-triyl unit and an N(CO)R- unit forming a twelve-membered ring.

Azepines↗
PubMedDate not supplied

New pregnane-type steroidal alkaloids from Sarcocca saligna and their cholinesterase inhibitory activity.

Five new steroidal alkaloids, 5,14-dehydro-N(a)-demethylsaracodine [3beta-N(a)-methyl-20S-N(b)-acetyl-N(b)-methylamino-pregn-5,14-diene] (1), 14-dehydro-N(a)-demethylsaracodine [3beta-N(a)-methyl-20S-N(b)-acetyl-N(b)-methylamino-5alpha-pregn-14-ene] (2), 16-dehydrosarcorine [(20S)-20-(N,N-dimethylamino)-3beta-(N(a)-acetylamido)-5alpha-pregn-16-ene] (3), 2,3-dehydrosarsalignone [(20S)-20-(N,N-dimethylamino)-3beta-(tigloylamino)-pregn-2,5-diene-4-one] (4), and 14,15-dehydrosarcovagine-D [(20S)-20-(N,N-dimethylamino)-3beta-(tigloylamino)-5alpha-pregn-2,14-diene-4-one] (5), were isolated from the ethanolic extract of Sarcococca saligna, along with two known bases, sarcovagenine-C (6) and salignarine-C (7). Their structures were elucidated on the basis of spectroscopic methods. All seven compounds were found to possess cholinesterase inhibitory potential in a concentration-dependent manner with the IC50 values ranging from 12.5 to 200 microM against acetylcholinesterase and from 1.25 to 32.2 microM against butyrylcholinesterase.

Alkaloids↗
PubMedDate not supplied

A diterpenoid lactone from Aplysia juliana.

A new diterpenoid lactone, angasiol acetate [1], has been isolated from the sea hare Aplysia juliana collected from the Karachi coastline of the Arabian ocean. The structure, including the absolute configuration of 1, was determined by single-crystal X-ray diffraction and spectroscopic techniques.

Animals↗