I= PHYTOCHEMICAL STUDIES ON THE STEROIDAL AND TRITERPENOIDAL CONSTITUENTS OF BUXUS HYRCANA AND JUNIPERUS COMMUNIS
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Title of Thesis
PHYTOCHEMICAL STUDIES ON THE STEROIDAL AND TRITERPENOIDAL CONSTITUENTS OF BUXUS HYRCANA AND JUNIPERUS COMMUNIS

Author(s)
Salma Shahnaz
Institute/University/Department Details
H.E.J. Research Institute of Chemistry/ University of Karachi
Session
2006
Subject
Chemistry
Number of Pages
171
Keywords (Extracted from title, table of contents and abstract of thesis)
buxus hyrcana, juniperus communis, triterpenoidal alkaloids, n- benzoy lbuxahyrcanine, n- tigloylbuxahyrcanine, n-isobutyroylbuxahyrcanine, hyrcanone, hyrcanol, hyrcatrienine, nb-dimethylcycloxobuxoviricine, hyrcamine, buxidin, buxandrine, buxabenzacinine, cyclomicrobuxinine, cyclomicrobuxine, e-buxenone

Abstract
This dissertation elaborates the phytochemical investigation of two plants Buxus hyrcana Pojark. and Juniperus communis L. This work has resulted in the isolation of eight new compounds, along with several known constituents.

Part A of the thesis comprises of the isolation and structure elucidation of natural products from B. hyrcana, a plant of Iranian origin. This includes eight new and six known triterpenoidal alkaloids, which are listed below:

New Natural Products N- Benzoy lbuxahyrcanine (33) N- Tigloylbuxahyrcanine (56) N-Isobutyroylbuxahyrcanine (94) Hyrcanone (95) Hyrcanol (96) Hyrcatrienine (97) Nb-Dimethylcycloxobuxoviricine (98) Hyrcamine (99)

Known Natural Products Buxidin (100) Buxandrine (101) Buxabenzacinine (102) Cyclomicrobuxinine (103) Cyclomicrobuxine (104) E-Buxenone (105)

Compounds 100-102 and 105 were isolated for the first time from B. hyrcana. The new compounds 33 and 56 were subjected to single-crystal X-Ray diffraction studies. This led to the determination of stereochemistry of tertiary OH group and configuration at C-20 position. These triterpenoidal alkaloids were tested for their antiacetylcholinesterase and anti butyryl cholinesterase activities and were found to be selective inhibitors of these enzymes. All tested compounds were more active against butyrylcholinesterase as compared to acetylcholinesterase.

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Part B of the thesis comprises of the isolation and structure elucidation of natural products from, Juniperus communis L. This includes two known compounds, which are β-sitosterol(109) and 3-O- β-D-glucopyranosyl- β-sitosterol(110).

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Download Full Thesis
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S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
327.85 KB
2 1 General Introduction 1
85.43 KB
3 2 Part-A Phytochemical Studies On Triterpenoidal Alkaloids Of Busus Hyrcana Pojark 4
5150.12 KB
  2.1 Introduction 4
  2.2 Results And Discussion 45
  2.3 Cholinesterase Inhibition Studies 117
  2.4 Experimental 126
  2.5 References 145
4 3 Part-B Phytochemical Studies On Secondary Metabolites From Juniperus Communis L. 145
320.53 KB
  3.1 Introduction 156
  3.2 Research And Discussion 161
  3.3 Experimental 162
  3.4 References 166
5 4 Glossary 168
96.07 KB
6 5 List Of Publications 171
15.34 KB