High field NMR spectroscopic studies of arteannuin B and a reappraisal of the structure of arteannuin C

1991 ◽  
Vol 30 (10) ◽  
pp. 3469-3471 ◽  
Author(s):  
P.K. Agrawal ◽  
R.A. Vishwakarma ◽  
D.C. Jain ◽  
R. Roy
2017 ◽  
Vol 15 (2) ◽  
pp. 151-154 ◽  
Author(s):  
Tahmid Faisal ◽  
Monira Ahsan ◽  
Jakir Ahmed Choudhury ◽  
ATM Zafrul Azam

The methanol extract of the powdered leaf of Eurya acuminata was investigated for isolation of secondary metabolites and two compounds were obtained by using VLC, column chromatography and TLC. The compounds were identified as phytol (1) and ?-sitosterol by extensive spectroscopic studies, including high field NMR analyses as well as co-TLC with authentic samples. The methanol extract of leaf of E. acuminata and its organic and aqueous soluble partitioning materials were evaluated for cytotoxic, thrombolytic and antimicrobial properties. In the cytotoxicity study the aqueous fraction of crude methanolic extract showed significant lethality towards brine shrimp having LC50 value 8.821 ?g/ml as compared to standard vincristine sulfate (0.404 ?g/ml). In the study for thrombolytic property, different extract of E. acuminata exhibited various thrombolytic activity ranging from 13.66 to 31.89 % as compared to standard streptokinase (46.51 %). No antimicrobial activity was observed from leaf extracts.Dhaka Univ. J. Pharm. Sci. 15(2): 151-154, 2016 (December)


1990 ◽  
Vol 271 (1) ◽  
pp. 243-245 ◽  
Author(s):  
I A Nieduszynski ◽  
T N Huckerby ◽  
J M Dickenson ◽  
G M Brown ◽  
G H Tai ◽  
...  

High-field 1H-n.m.r.-spectroscopic studies supported by chemical carbohydrate analyses show that skeletal keratan sulphates (KS-II) of bovine origin may be sub-classified into two groups. Keratan sulphate chains from articular and intervertebral-disc cartilage (KS-II-A) contain two structural features, namely alpha(1----3)-fucose and alpha(2----6)-linked N-acetyl-neuraminic acid residues, that are absent from keratan sulphates from tracheal or nasal-septum cartilage (KS-II-B).


Author(s):  
Mohammad S Rahman ◽  
Rasheduzzaman Chowdhury ◽  
Chodhury M Hasan ◽  
Mohammad A Rashid

Two oleanane-type glycosides eclalbasaponin II (1) and eclalbasaponin I (2) along with the ubiquitous steroid, stigmasterol were isolated from an n-hexane extract of the stem bark of Eclipta prostrata. The structures of the isolated compounds were confirmed by extensive spectroscopic studies, notably high field NMR and MS. The 13C NMR data of the parent saponins 1 and 2 are reported here for the first time. Key words: Eclipta prostrata, Compositae, Oleanane glycoside, Eclalbasaponin I, Eclalbasaponin II. Dhaka Univ. J. Pharm. Sci. Vol.4(2) 2005 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website


2021 ◽  
Vol 44 (2) ◽  
pp. 85-93
Author(s):  
Mohammad Shahriar Shahriar ◽  
Mohiuddin Ahmed Bhuiyan ◽  
Md Sohel Rana

Six coumarins, one benzene, one flavone, one acridone, one limonoid, one triterpene and two phytosterol derivatives were isolated from the methanol, ethanol and chloroform leaf extracts of Citrus assamensis. Extensive spectroscopic studies, including high field 1H NMR and 13C NMR analyses, allowed the identification of thirteen known compounds as bergapten (1), umckalin (2), citropten (3), 4-hydroxybenzaldehyde (4), bergamottin (5), β-amyrin (6), umbeliferone (7), scopoletin (8), citrusinol (9), citracridone-III (10), limonin (11), stigmasterol (12), and β-sitosterol (13). The identity of these compounds was confirmed by comparison with published data as well as co-TLC with authentic samples. Journal of Bangladesh Academy of Sciences, Vol. 44, No. 2, 85-93, 2020


Author(s):  
Mohammad S Rahman ◽  
Rasheduzzaman Chowdhury ◽  
Bilkis Begum ◽  
Khondaker M Rahman ◽  
Mohammad A Rashid

Five compounds were isolated from a hexane extract of the stem bark of Amoora cucullata. The structures of the isolated compounds were established as fridelin (1), stigmasterol, β-sitosterol, betulinic acid (2) and caffeic acid (3) by extensive spectroscopic studies, including high field NMR and MS analyses. This is the first report of occurrence of these compounds from A. cucullata. Key words: Amoora cucullata, Meliaceae, Fridelin, Betulinic acid, Caffeic acid, β-Sitosterol, Stigmasterol Dhaka Univ. J. Pharm. Sci. Vol.4(1) 2005 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website


Sign in / Sign up

Export Citation Format

Share Document