I= ISOLATION AND STRUCTURAL STUDIES ON THE CHEMICAL CONSTITUENTS OF BUXUS PAPILLOSA AND THE RELATED PLANTS
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Title of Thesis
ISOLATION AND STRUCTURAL STUDIES ON THE CHEMICAL CONSTITUENTS OF BUXUS PAPILLOSA AND THE RELATED PLANTS

Author(s)
Habib Nasir
Institute/University/Department Details
University of Karachi/ H.E.J. Research Institute of Chemistry
Session
1993
Subject
Chemistry
Number of Pages
189
Keywords (Extracted from title, table of contents and abstract of thesis)
buxus papillosa, buxus hildebrandtii, triterpenoids: buxapentalactone (1), buxahejrine (2), buxatenone (3), 11a-hydroxybuxatenone (4), buxaheptalactone (5), buxapapillosion (6)

Abstract
The work described in this thesis is based on the studies on the chemical constituents of Buxus papillosa and Buxus hildebrandtii. B. papillosa is large shrub found in the northern areas of Pakistan. Previous work on the leaves of this plant by Atta-ur-Rehman et al. has resulted in the isolation of more than 60 new alkaloids. The present work on the roots of B. popillosa has led to the isolation of six new non-nitrogenous triterpenoids: buxapentalactone (1). Buxahejrine (2). Buxatenone (3). 11a-hydroxybuxatenone (4). Buxaheptalactone (5) and buxapapillosion (6).

Buxus hildebrandtii is a native of Bale province. Ethiopia. Phtochemical investigations on the leaves of this plant have resulted in the isolation of ten alkaloids (four new and six with new source): 30-O-benzoyl-16-deoxybuxidienine-C (7) Nb-demethyl-30-O-benzoy1-16-deoxybuxidienine-C (8). 30-norbuxamine-A (9). 30-hydroxybuxamine-A (10), buxamine-A (11), cyclorolfeine (12), moenjodaramine (13), buxamine-C (14), cyclomicrobuxamine (15) and cyclobuxo-viridine (16). Modern spectroscopic techniques (X-ray. ID NMR, 2D NMR, EIMS, HREIMS, FD, FAB, UV and IR) were used to establish the structures of the above mentioned compounds.

Download Full Thesis
1143.87 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents/ Summary
81.95 KB
2 1 General Introduction 1
228.03 KB
  1.1 History of natural product chemistry 1
  1.2 Terpenes 8
  1.3 Alkaloids 19
3 2 Biosynthesis 36
136.15 KB
  2.1 Introduction 36
  2.2 Biosynthesis of triterpenes 37
  2.3 Biosynthesis of Buxus alkaloids 50
4 3 Results and Discussion 56
612.36 KB
  3.1 Introduction 56
  3.2 Triterpenes from the roots of Bxus papillosa 59
  3.3 Alkaloids from the roots of Buxus hildebrandtii 118
5 4 Experimental 143
229.08 KB
  4.1 General Experimental Detail 143
  4.2 Buxus papillos 145
  4.3 Buxus hildebrandtii 157
6 5 References 178
86.49 KB