Two new 2'-oxygenated flavones from Andrographis elongata

Phytochemistry, Pharmacology and Clinical Use of Andrographis paniculata

Andrographis paniculata (Burma f.) Wall ex Nees (Acanthaceae) is a common weed distributed throughout the tropical and subtropical regions. All parts of A. paniculata are extremely bitter in taste. This plant is well known in Siddha, Ayurvedic and traditional (tribal) systems of medicine in India. A. paniculata is used for the treatment of infectious diseases, which account for the major proportion of health problems, and which are most often used in the traditional system of medicine. The major active components of the plant are andrographiloids, which have been extensively studied in a variety of models including human clinical trials for their therapeutic effects. Moreover, A. paniculata is known to have very low toxicity in animals and humans. The plant also exhibits antifertility effects. Most of the traditional uses of the species have some scientific basis. This review is an attempt to summarize the available information on A. paniculata for further investigation.

A New Geranylated Chalcone from Andrographis Lobelioides

A new O-geranylated chalcone, 2′-hydroxy-2-methoxy-4′- O-[( E)-3,7-dimethyl-2,6-octadienyl] chalcone (1), together with three known flavones, 5-hydroxy-7,2′-dimethoxyflavone (2), skullcapflavone I (3) and echioidin (4), were isolated from the leaves of Andrographis lobelioides. The structure of 1 and the known compounds (2–4) were achieved by extensive 1D and 2D NMR spectral and chemical studies.

A New Diacylated Labdane Diterpenoid from Andrographis wightiana

A new acylated labdane diterpenoid, 14-deoxy-3,19-diacetyl-11,12-didehydroandrographolide (1), together with three known labdane diterpenoids, wightionolide (2), andrographolide (3) and neoandrographolide (4), and three known flavones, echioidinin (5), skullcapflavone I 2′-methyl ether (6) and echioidin (7), were isolated from the whole plant of Andrographis wightiana. The structure of compound 1 was elucidated by 1D and extensive 2D-NMR spectral studies.

A randomized double blind placebo controlled clinical evaluation of extract of Andrographis paniculata (KalmCold) in patients with uncomplicated upper respiratory tract infection

A randomized, double blind placebo controlled clinical study was conducted to evaluate the efficacy of KalmCold, an extract of Andrographis paniculata, in patients with uncomplicated upper respiratory tract infection (URTI). The assessment involved quantification of symptom scores by Visual Analogue Scale. Nine self evaluated symptoms of cough, expectoration, nasal discharge, headache, fever, sore throat, earache, malaise/fatigue and sleep disturbance were scored. A total of 223 patients of both sexes were randomized in two groups which received either KalmCold (200 mg/day) or placebo in a double blind manner. In both the treatments, mean scores of all symptoms showed a decreasing trend from day 1 to day 3 but from day 3 to day 5 most of the symptoms in placebo treated group either remained unchanged (cough, headache and earache) or got aggravated (sore throat and sleep disturbance) whereas in KalmCold treated group all symptoms showed a decreasing trend. Within groups, mean scores of symptoms in both the groups decreased significantly (p < or = 0.05) from day 1 to day 3 and day 5 while from day 3 to day 5 all symptoms except expectoration in placebo group did not improve significantly whereas in KalmCold treated group all symptoms improved significantly (p < or = 0.05) except earache. Comparing mean between both groups, all symptoms at day 1 and day 3 were found to be the same while at day 5 all symptoms except earache in KalmCold treated group improved significantly (p < or = 0.05) than placebo group. Similarly, within groups, overall scores of all symptoms in both the groups decreased significantly (p < or = 0.05) from day 1 to day 3 and day 5 while from day 3 to day 5 placebo group did not improve significantly whereas KalmCold treated group showed significant improvement (p < or = 0.05). On between groups analysis, KalmCold group showed significant reduction (p < or = 0.05) in overall symptom scores as compared to placebo group. In both placebo and KalmCold treated groups, there were only a few minor adverse effects with no significant difference in occurrence (Z = 0.63; p > 0.05). The comparison of overall efficacy of KalmCold over placebo was found to be significant (p < or = 0.05) and it was 2.1 times (52.7%) higher than placebo. The findings of this study revealed that KalmCold was effective in reducing symptoms of upper respiratory tract infection.

A new acylated flavone glycoside from Colebrookea oppositifolia

A new acylated flavone glycoside, echioidinin 2'-O-beta-D-(2''-O-acetyl)glucopyranoside (1) along with the three known flavonoids, 5,6,7,8,5'-pentamethoxy-3',4'-methylenedioxyflavone (2), 5,2',6'-trihydroxy-7-methoxyflavone (3), and kaempferol 7,4'-dimethyl ether 3-O-beta-D-glucopyranoside (4), were isolated from the roots of Colebrookea oppositifolia. The structure of compound 1 was elucidated by extensive spectral and chemical studies.

A Novel Acylated Flavone Glycoside from Andrographis nallamalayana

A new acylated flavone glycoside, skullcapflavone I 2′- O-β-D-(6″- E-cinnamoyl) glucopyranoside (1), together with two known flavones, 5,2′-dihydroxy-7-methoxyflavone (2) and 5,2′,6′-trihydroxy-7-methoxyflavone-2′- O-β-D-glucopyranoside (3), and two known labdane diterpenoids, 14-deoxy-11,12-didehydroandrographolide (4) and andrographolide (5) were isolated from the whole plant of Andrographis nallamalayana. Structural elucidation of the new compound, as well as of the known compounds was achieved by various NMR techniques including 1H-1H COSY, HSQC, HMBC and ROESY experiments, ESITOF mass spectrometry, acid hydrolysis and saponification studies.

Raddeanalin, a new flavonoid glycoside from the leaves of Salix raddeana Laksh

A new flavonoid glycoside, diosmetin 7-O-beta-D-xylopyranosyl(1-6)-beta-D-glucopyranoside, named raddeanalin (1), was isolated from the ethanolic extract of the leaves of Salix raddeana Laksh. together with three known compounds, kaempferol 3-O-glucoside (2), quercetin 3-O-glucoside (3) and quercetin 3-O-rutinoside (4). The structure of new compound was established by the spectral data and chemical properties.

A new chalcone and a flavone from Andrographis neesiana

Two new flavonoids, 2',4',6',2,3,4-hexamethoxychalcone (1) and 5-hydroxy-7,2',5'-trimethoxyflavone (2) together with a known flavone glycoside, echioidinin 5-O-beta-D-glucopyranoside (3) were isolated from the whole plant of Andrographis neesiana, and the structures were elucidated by electrospray ionization tandem mass spectrometry (ESI-MS/MS) and one- and two-dimensional (1D- and 2D)-NMR spectral studies including 1H-1H correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC) and nuclear Overhauser enhancement spectroscopy (NOESY) experiments.

Flavonoids from Andrographis lineata

Three flavonoids, 5,7,2',3',4'-pentamethoxyflavone (1), 2'-hydroxy-2,4',6'-tri methoxychalcone (2) and dihydroskullcapflavone I (3), together with 17,19,20-trihydroxy-5beta, 8alpha H, 9beta H,10alpha-labd-13-en-16,15-olactone (4), a known diterpenoid and six known flavonoids, 5-hydroxy-7,8-dimethoxyflavanone (5), 5-hydroxy-7,8,2',3',4'-pentamethoxyflavone (6), 5,2'-dihydroxy-7-methoxyflavanone (7), 5,2'-dihydroxy-7,8-dimethoxyflavone (8), 5,2'-dihydroxy-7-methoxyflavone (9) and 5,2'-dihydroxy-7-methoxyflavone 2'-O-beta-D-glucopyranoside (10) were isolated from the whole plant of Andrographis lineata. The structures of these compounds were elucidated on the basis of spectral and chemical studies.

A flavone and an unusual 23-carbon terpenoid from Andrographis paniculata

Phytochemical investigation of the roots and aerial parts of Andrographis paniculata Nees yielded a new flavone, 5-hydroxy-7,2',6'-trimethoxyflavone and an unusual 23-carbon terpenoid, 14-deoxy-15-isopropylidene-11,12-didehydroandrographolide together with five known flavonoids and four known diterpenoids. The structures of these compounds were determined on the basis of spectral and chemical studies.

New 2'-oxygenated flavonoids from Andrographis affinis

Three new 2'-oxygenated flavonoids, (2S)-5,7,2',3',4'-pentamethoxyflavanone (1), 5-hydroxy-7,8,2',5'-tetramethoxyflavone (2), and echioidinin 2'-O-beta-d-(6' '-O-acetyl) glucopyranoside (3), together with four known flavonoids, 7-O-methyldihydrowogonin, 7-O-methylwogonin, skullcapflavone I 2'-methyl ether, and skullcapflavone I, and two diterpenoids, andrograpanin and 14-deoxy-11,12-didehydroandrographolide, were isolated from the whole plant of Andrographis affinis. The structures were elucidated by spectral and chemical studies.

Two new flavonoids from Andrographis rothii

Two new flavonoids, 5, 7, 2', 5'-tetramethoxyflavanone (1) and 5-hydroxy-7, 2'-dimethoxyflavone (2), together with two known flavones, skullcapflavone I (3) and echioidin (4) were isolated from the whole plant of Andrographis rothii. The structures of the new compounds were established by extensive one- and two-dimensional (1D- and 2D-) NMR spectral studies.

Flavonoids from Andrographis viscosula

Phytochemical investigation of the whole plant of Andrographis viscosula has led to the isolation of three new 2'-oxygenated flavonoids, (2R)-5-hydroxy-7,2',3'-trimethoxyflavanone (1), 7,2',5'-trimethoxyflavone (2), 5,7,2',3'-tetramethoxyflavone (3), and eight known flavones, 5,7,2'-trimethoxyflavone (4), 5,7,2',4',5'-pentamethoxyflavone (5), echioidinin (6), 5,2',6'-trihydroxy-7-methoxyflavone (7), 5-hydroxy-7,2'-dimethoxyflavone (8), echioidin (9), echioidinin 5-O-glucoside (10), and 5,2',6'-trihydroxy-7-methoxyflavone 2'-O-glucoside (11). The structures of 1-11 were elucidated by physical and spectral methods, including extensive 2D NMR studies. The presence of 2'-oxygenated flavonoids is apparently restricted to Andrographis species in Acanthaceae. Therefore, 2'-oxygenated flavonoids are regarded as chemotaxonomic markers of Andrographis genus in the Acanthaceae family.

Flavones from Andrographis viscosula

Two new 2'-oxygenated flavones, 5,7,2'-trimethoxyflavone (1). and 5,7,2',4',6'-pentamethoxyflavone (2). were isolated from the whole plant of Andrographis viscosula along with three known flavones, echioidinin (3). 5,2',6'-trihydroxy-7-methoxyflavone (4). and echioidin (5). The structures of these compounds were elucidated on the basis of 1D and 2D NMR spectral studies.