Glycolone,a quinolone alkaloid from Glycosmis pentaphylla

Glycolone, a quinolone alkaloid has been isolated from the leaves of Glycosmis pentaphylla. The structure of the compound has been established as 4,8-dimethoxy-3-(3-methyl but-2-enyl)-2-quinolone from physical and chemical evidences.     

Glycozolidol,an antibacterial carbazole alkaloid from Glycosmis pentaphylla

Glycozolidol, a new carbazole alkaloid, has been isolated from the roots of Glycosmis pentaphylla. Its structure has been established as 6-hydroxy-2-methoxy-3-methylcarbazole on the basis of physical and chemical evidence. The compound has been found to be active at some Gram-positive and Gram-negative bacteria.     

Glycozolinine,a carbazole derivative from Glycosmis pentaphilla

A new carbazole derivative, glycozolinine, was isolated from the seeds of Glycosmis pentaphylla. From physical and chemical evidence its structure is 6-hydroxy-3-methylcarbazole.     

Kokusaginine and evolitrine from Acronychia pedunculata

Kokusaginine and evolitrine are the major alkaloids present in Sri Lankan Acronychia pedunculata. The Indian variety of Acronychia laurifolia collected in Madras does not contain these alkaloids.     

Zanoxyline—a new alkaloid from stem bark of Zanthoxylum oxyphyllum

The EtOH extract of stem bark of Zanthoxylum oxyphyllum yielded rhetsinine and a new alkaloid 1-(4′methoxy benzyl)-6,7-dimethoxy N:N dimethyl 1,2,3,4 tetrahydroisoquinolinium hydroxide provisionally named zanoxyline.     

Muellitol,a novel trialkenyl inositol from Evodiella muelleri

Muellitol has been isolated from the leaves of Evodiella muelleri and the structure established as 1,3,5-tri-(3-methyl-2-butenyl)cyclohexane-r-1-t-2-c-3-t-4-c-5-t-6-hexol. Chemical and spectroscopic examination of the compound and its derivatives showed it to be conformationally similar to scyllitol. This is the first report of the natural occurrence of a triprenylinositol.     

Nupharopumiline,a new quinolizine alkaloid from Nuphar pumila

A new quinolizine alkaloid, (+)-nupharopumiline, has been isolated from the rhizomes of Nuphar pumila. It has been shown by spectroscopic and chemi     

Helifoline,a pyrrolizidine alkaloid from Heliotropium ovalifolium

The alkaloidal fraction of Heliotropium ovalifolium yielded retronecine and the new pyrrolizidine alkaloid helifoline. Helifoline was formulated as 1α-angelyloxymethyl-8α-pyrrolizidine-2β,7β-diol on the basis of spectroscopic measurements and hydrolysis to the necine base which appears to be identical with croalbinecine.     

Some minor constituents from Glycosmis pentaphylla

A quinazolone alkaloid, glycophymine and an amide, glycomide have been isolated from Glycosmis pentaphylla.     

New alkaloids from Glycosmis mauritiana

Chemical investigation of the roots of G. mauritiana resulted in the isolation of two new alkaloids; 1-hydroxy-3-methoxy-2-(3-methylbut-2-enyl)-N-methylacridan-9-one (1) and 4,8-dimethoxy-3-(3-methylbut-2-enyl)-N-methyl-2-quinolone (6). The structures of these new bases have been established by chemical and spectroscopic methods and confirmed in the case of 6 by its synthesis. Interestingly, the formic acid-catalysed cyclisation of 1 gave the dealkylated product 3 along with the pyrano-[2, 3-a]-acridine (4).     

Piplartine-dimer A,a new alkaloid from Piper tuberculatum

Piplartine-dimer A (1), a dimer of the known pyridone alkaloid piplartine, was isolated from root bark of Piper tuberculatum. It is accompanied by piplartine (3) and 3,4,5-trimethoxycinnamic acid.     

Strychnozairine,an indole alkaloid from Strychnos variabilis

Through a combination of spectroscopic techniques (UV, IR, mass spectrometry and NMR) it has been possible to show that strychnozairine, an alkaloid isolated from the root bark of Strychnos variabilis, is N₁-acetyl-16-R-formyl-19-oxo-20,21-didehydrostrychnane.     

Alkaloids from Glycosmis cochinchinensis twigs

A phytochemical investigation of the twigs of Glycosmis cochinchinensis led to the isolation of two new alkaloids, glycosmisacridone (1) and glycosmisindole (2), together with eight known compounds (3–10). Their structures were elucidated by intensive analysis of their spectroscopic data. Compound 9 exhibited moderate antibacterial activity against methicillin-resistant Staphylococcus aureus SK1with an MIC value of 16 μg/mL.     

Vasicol,a new alkaloid from Adhatoda vasica

A novel alkaloid isolated from the roots of Adhatoda vasica has been characterized as 1,2,3,4,9,11 hexahydro pyrrolo (2,1-b) quinazolin-3,11 diol by chemical and spectroscopic methods. Vasicinone has also been isolated from the roots of this plant.     

16-Epivenenatine and 16-epialstovenine,new stereomers from Alstonia venenata

16-Epivenenatine and 16-epialstovenine have been isolated from Alstonia venenata. The structures and stereochemistry of these two new bases have been determined from spectral analysis, chemical studies and correlation experiments with venenatine and alstovenine.