I= ISOLATION AND STRUCTURAL STUDIES ON THE ALKALOIDS OF SOME INDIGENOUS MEDICINAL PLANTS BUXUS PAPILOSA. CATHARANTHUS ROSEUS AND CISSAMPELOS PAREIRA
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Title of Thesis
ISOLATION AND STRUCTURAL STUDIES ON THE ALKALOIDS OF SOME INDIGENOUS MEDICINAL PLANTS BUXUS PAPILOSA. CATHARANTHUS ROSEUS AND CISSAMPELOS PAREIRA

Author(s)
Muhammad Iqbal Choudhary
Institute/University/Department Details
University of Karachi/H.E.J Research Institute of Chemistry
Session
1987
Subject
Chemistry
Number of Pages
281
Keywords (Extracted from title, table of contents and abstract of thesis)
alkaloids, medicinal plants, buxus papilosa, catharanthus roseus, cissampelos pareira, buxus alkaloids, norcurine

Abstract
This thesis presents the work on three medicinal plants of Pakistani origin. Part A describes the studies on the leaves of Buxus papilosa. Investigation on the alkaloidal contents of the leaves of B.papilosa have led to the isolation and characterization of twenty two new steroidal bases. In addition, three more alkaloids have also been reported for the first time from this plant. A separate chapter in the introduction section of Part A describes some spectral generalizations made for Buxus alkaloids based on a thorough literature search and personal observations. These generalizations provide valuable information for checking the proposed structures. Biosynthetic routes to various types of Buxus alkaloids are also proposed in the introduction section of Part A.

New Steridal Alkaloids from Buxus Papilosa i(+)-Buxaquamarine (53) ii(-)-Cyclobuxoviricine (54) iii(-)-Cycloxobuxoviricine (55) iv(-)-31-Acetoxy-Na-Benzoylbuxidienine (56) v(+)-N-Benzoyl-16α-acetoxycloxobuxidine-F (57) vi(+)-Buxabenzamidienine (58) vii(+)-16-α-Acetoxybuxabenzamidienine (59) viii(+)-Buxotrienine (60) ix(-)-Buxanoldine (61) x(+)-Buxanaldinine (62) xi(+)-Buxabenzamidine (63) xii(+)-Homobuxaquamarine (64) xiii(+)-Norcyclomicrobuxeine (65) xiv(+)-Buupapine (66) xv(+)-Nb-Norbuxupapine (67) xvi(+)-Buxaprogestine (68) xvii(-)-Buxapapinolamine (69) xviii(-)-E-Cyclobuxaphylamine (70) xix(-)-Z-Cyclobuxaphylamine (71) xx(+)-N-Formylharappamine (72) xxi(+)-N-Formylpapilicine (73) xxii(+)-N-Formylcyclomicrobuxeine (74)

Known Alkaloids Isolated for the First Time from Buxus Papilosa i(+)-Buxaminol-B (75) iiCyclobuxoviridine (76) iii(+)-N-Benzoylcycloxobuxidine-F (77) and iv(+)-Sinapic acid methyl ester (78)

Part B of the thesis describes studies on the alkaloidal constituents of Catharanthus roses which have resulted in the isolation of the two new indole alkaloids. One of them, namely (-)-bannucine, is the first Aspidosperma alkaloid bearing a five-membered lactam ring. A known dimeric alkaloid, Catharine, which was not reported from C. roseus was also islated and detailed temperature-dependent NMR experiments confirmed its existence in two non-separable conformers. Detailed mass and 13C-NMR studies on (-)-cathovaline, another unreported alkaloid from C.roseus, have been carried out. The following alkaloids were thus isolated from C.roses

New Indole Alkaloids from Catharanthus Roseus i(+)-Rosamine (4) ii(-)-Bannucine (5)

Known Alkaloids Isolated for the first time from Catharanthus Roseus iCatharine (6) iiCathovaline (7)

Part C of the thesis presents work done on the aerial parts of Cissampelos pareira, which resulted in the isolation of a new bisbenzylisoquinoline alkaloid norcurine (8).

Modern spectroscopic methods were employed to determine their structures including two-dimesional NMR experiment (2D J resolved, COSY 45°, NOESY). DEPT and GASPE experiments were carried out to determine the multiplicities of various carbon atoms. The stereochemistry of various asymmetric centers was established by extensive NOE difference studies.

Download Full Thesis
1823.49 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
100.07 KB
2 1 General Introduction 4
28.78 KB
3 2 Introduction 9
366.17 KB
  2.1 Steroidal Alkaloids 10
  2.2 Pharmacological Importance of Buxus Alkaloids 33
  2.3 Biosynthesis of Buxs Alkaloids 34
  2.4 Spectral Behaviour of Buxus Alkaloids 45
  2.5 Alkaloids from the Leaves of Buxus Papilosa 58
4 3 Results and Discussion 59
806.53 KB
  3.1 New Alkaloids from the Leaves of Buxus Papilosa 61
  3.2 Unreported Alkaloids from Buxus Papilosa 158
5 4 Experimental
273.34 KB
  4.1 General Notes 169
  4.2 Plant Material 170
  4.3 Extraction and Purification 171
  4.4 Alkaloids from the Leaves of Buxus Papilosa 176
6 5 References(PART – A) 199
74.71 KB
7 6 Introduction 207
51.72 KB
  6.1 Indole Alkaloids 208
  6.2 Catharanthus Roseus 215
8 7 Results and Discussion 216
228.65 KB
  7.1 New Alkaloids from Catharanthus Roseus 217
  7.2 nreported Alkaloids from Catharanthus Roseus 235
9 8 Experimental 247
68.18 KB
  8.1 General Notes 248
  8.2 Plant Material 249
  8.3 Extraction and Purification 250
  8.4 Alkaloids from the Leaves of Catharanthus Roseus 252
10 9 References (PART – B) 256
33.32 KB
11 10 Introduction 261
61.04 KB
  10.1 The Benzylisoquinoline Alkaloids 262
  10.2 Cissampelos Pareira 268
12 11 Results and Discussion 271
23.15 KB
  11.1 Norcurine (8)
13 12 Experimental 275
15.46 KB
  12.1 Norcurine (8) 276
14 13 References (PART – C) 277
15.6 KB