Ahmed Abbaskhan
University of Karachi
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Publication
Featured researches published by Ahmed Abbaskhan.
Journal of Natural Products | 2008
M. Iqbal Choudhary; Saleem Jan; Ahmed Abbaskhan; Syed Ghulam Musharraf; Samreen; Samina A. Sattar; Atta-ur-Rahman
Three new cycloartane glycosides have been isolated from Astragalus bicuspis. They were identified as 6alpha-hydroxy-3-O-beta-xylopyranosyloxy-24,25,26,27-tetranor-9,19-cyclolanosta-16,23-lactone (1), 6alpha-hydroxy-23-methoxy-16beta,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-beta-xyloside (2), and 23(R),24(S),25(R),26(S)-16beta/23,23/26,24/25-triepoxy-6alpha,26-dihydroxy-9,19-cyclolanosta-3-O-beta-xyloside (3), on the basis of their spectroscopic data. Two known cycloartane derivatives, 4 and 5, were also obtained from this plant. Compounds 2-5 were tested for leishmanicidal activity against Leishmania major promastigotes and for cytotoxicity against 3T3 cancer cells.
Chemistry & Biodiversity | 2008
M. Iqbal Choudhary; Afshan Begum; Ahmed Abbaskhan; Syed Ghulam Musharraf; Asma Ejaz; Atta-ur-Rahman
Two new phenylpropanoids were isolated from Lindelofia stylosa (Kar. and Kir.) and characterized as 4‐hydroxy‐N‐{4‐[(E)‐3‐(4‐hydroxy‐3‐methoxyphenyl)prop‐2‐enamido]butyl}benzamide (1) and 2‐[3‐hydroxy‐4‐(4‐hydroxyphenoxy)phenyl]‐1‐(methoxycarbonyl)ethyl (E)‐3‐(3,4‐dihydroxyphenyl)prop‐2‐enoate (2). Four known compounds, i.e. two phenylpropanoids, p‐coumaric acid (=(E)‐3‐(4‐hydroxyphenyl)prop‐2‐enoic acid; 3) and ferulic acid (=(E)‐3‐(4‐hydroxy‐3‐methoxyphenyl)prop‐2‐enoic acid; 4), and two naphthalene glycosides, 8‐O‐β‐D‐glucopyranosyltorachrysone (5) and 8‐O‐β‐D‐glucopyranosyl‐6‐demethoxytorachrysone (6), were also isolated for the first time from the plant. Compounds 1–6 were subjected to various antioxidant assays, including DPPH radical‐ and superoxide anion‐scavenging, and Fe2+‐chelation assays. Compound 2 was found to be most active in all assays with potency nearly similar to that of propyl gallate. Besides 2, compounds 1 and 5 were also found to be active in DPPH radical‐scavenging standard assay.
Phytotherapy Research | 2012
Ahmed Abbaskhan; Muhammed Iqbal Choudhary; Mohammed Nabeel Ghayur; Zeba Parween; Farzana Shaheen; Anwarul Hassan Gilani; Takuro Maruyama; Kiran Iqbal; Yoshisuke Tsuda
In continuation of our work on Indian celery (Seseli diffusum (Roxb. ex Sm.) Santapau & Wagh; Umbelliferae), the fractionation of the 80% MeOH–H2O extract of the seeds was performed to identify the principles responsible for its folk use as an antispasmodic and diuretic. Several compounds were isolated as active components: seselin (1) and anthriscinol methyl ether (4) showed a selective cytotoxicity to some yeast strains. Compound 1 also showed spasmolytic activity. On the other hand, isopimpinellin (3) and isorutarin (5) exhibited a spasmogenic effect on the smooth muscle preparations. Compound 5 was also found to have antioxidant activity. Among them, compound 4 was isolated for the first time from this plant. Copyright
Heterocycles | 2010
Atta-ur-Rahman; Sumaira Hareem; M. Iqbal Choudhary; Bilge Sener; Ahmed Abbaskhan; Hina Siddiqui; Shazia Anjum; Ilkay Erdogan Orhan; İlhan Gürbüz; Filiz Ayanoğlu
A new compound, 1,3-O-diferuloylsucrose (1), and a synthetically known compound, 5,7-dihydroxy-6-methoxychromone (2), along with several known natural products, irilone (3), 4�c ,5,7-trihydroxy-6-methoxyflavanone (4), tectorigenin (5), kaempferol (6), 4�c ,5,7-trihydroxy-3�c ,8-dimethoxyflavanone (7), 8-methoxyeriodictyol (8), hispidulin (9), and mangiferin (10) were isolated from the rhizomes of Iris unguicularis. Compounds 1, 6, 8 and 10 showed a considerable DPPH radicals scavenging activity. Their structures have been deduced through different spectroscopic techniques. The structure of compound 2 was also confirmed by single-crystal X-ray diffraction techniques as well.
Planta Medica | 2011
Saleem Jan; Ahmed Abbaskhan; Syed Ghulam Musharraf; Samina A. Sattar; Saud Resayes; Zeid Abdullah Alothman; Abdullah Mohammed Al-Majid; M.I. Choudhary
Three new cycloartane triterpenoids have been isolated from Astragalus bicUSPIS Fisch. Their structures were elucidated as 23(R),24(S),25( R),26(S)-16 β/23,23/26,24/25-triepoxy-26-hydroxy-9,19-cyclolanosta-3,6-dione (1), 6 α,23,24,25-tetraol-16 β-acetoxy-23(R),24(R)-9,19-cyclanosta-3-one (2), and 6 α,23,24,25-tetraol-16 β-acetoxy-23(R),24(R)-9,19-cyclolanosta-3 β- O-xyloside (3), based on their spectroscopic analysis. All cycloartane tritepenoids exhibited weak cytotoxicities against 3T3 fibroblast cells as compared to the standard drug cycloheximide. Compounds 3 and 4 were also tested for their antileishmanial potential, and a weak activity was observed against promastigotes of Leishmania major.
Journal of Natural Medicines | 2009
Takuro Maruyama; Ahmed Abbaskhan; Muhammad Iqbal Choudhary; Yoshisuke Tsuda; Yukihiro Goda; Michel Farille; Jean-Pierre Reduron
In the course of our study on the traditional medicines and foodstuffs used in Pakistan, we investigated the origin of Indian celery by using the analysis of the internal transcribed spacer (ITS) sequence of nuclear rDNA and a phytochemical approach. We found that the source plant of the Indian celery containing coumarin derivatives such as seselin (1), bergapten (2) and isopimpinellin (3) was not common celery, Apium graveolens. Our results suggest the source plant is Seseli diffusum even though Indian workers reported that A. graveolens seeds contain the aforementioned compounds. In addition, a market survey of the Indian celery in Pakistan and related countries revealed that the Indian celery seeds in Pakistani markets are mainly composed of three species which have been confused in rural markets.
Helvetica Chimica Acta | 2003
Khalid Mohammed Khan; Ghulam Murtaza Maharvi; Ahmed Abbaskhan; Safdar Hayat; Mahmud Tareq Hassan Khan; Talat Makhmoor; M. Iqbal Choudhary; Farzana Shaheen; Atta-ur-Rahman
Phytochemistry | 2008
M. Iqbal Choudhary; Nadra Naheed; Ahmed Abbaskhan; Syed Ghulam Musharraf; Hina Siddiqui; Atta-ur-Rahman
Phytochemistry | 2006
Balakyz Yeskaliyeva; M. Ahmed Mesaik; Ahmed Abbaskhan; Aisha Kulsoom; G. Sh. Burasheva; Zh. A. Abilov; M. Iqbal Choudhary; Atta-ur-Rahman
Natural Product Updates | 2010
M.I. Choudhary; Saima Maher; Afshan Begum; Ahmed Abbaskhan; Sajjad Ali; Ambreen Khan; Shafique-ur-Rehman; Atta-ur-Rahman