Naphthylisoquinoline Alkaloids: Structural Elucidation, Metabolism

201 Pages·2007·3.36 MB·English

by  Johan H Faber

Naphthylisoquinoline Alkaloids:
Structural Elucidation, Metabolism,
and Functional Analysis of their
Bioactivities

DISSERTATION ZUR ERLANGUNG DES
NATURWISSENSCHAFTLICHEN DOKTORGRADES
DER BAYERISCHEN JULIUS-MAXIMILIANS-UNIVERSITÄT WÜRZBURG

vorgelegt von
Johan Henrik Faber
aus
Kopenhagen,
Dänemark

Würzburg 2006
Eingereicht am: _______________________________________________________
bei der Fakultät für Chemie und Pharmazie

1. Gutachter: __________________________________________________________
2. Gutachter: __________________________________________________________
der Dissertation

1. Prüfer: _____________________________________________________________
2. Prüfer: _____________________________________________________________
3. Prüfer: _____________________________________________________________
des Öffentlichen Promotionskolloquiums

Tag des Öffentlichen Promotionskolloquiums: ______________________________

Doktorurkunde ausgehändigt am: ________________________________________
Die vorliegende Arbeit wurde in der Zeit von Februar 2002 bis September 2005
am Institut für Organische Chemie der Universität Würzburg angefertigt

Herrn Prof. Dr. Dr. h.c. G. Bringmann danke ich für
die hervorragende Unterstützung dieser Arbeit,
die freundliche Atmosphäre
und die exzellenten Arbeitsbedingungen

Teile der im Rahmen dieser Arbeit erzielten Ergebnisse waren bereits Gegenstand von
Publikationen[31,104,117,126,132,147,154,211,241] sowie von Postern und Vorträgen
2222222
Dedicated to my family
CONTENTS I

Contents
RESULTS AND DISCUSSION..................................................................1
1 Introduction.........................................................................................................................1
2 Mode of Action of Quinoline Antimalarial Drugs............................................................7
2.1 UV Spectroscopy........................................................................................................8
2.2 Structures of FPIX (9)-Quinoline Antimalarials in Solution....................................11
2.3 Further Spectroscopic Investigations........................................................................13
3 Isolation and Characterization of Naphthylisoquinoline Alkaloids from
Ancistrocladus tanzaniensis Cheek & Frimodt-Møller (Ancistrocladaceae)......15
3.1 Introduction...............................................................................................................15
3.2 A. tanzaniensis...........................................................................................................15
3.3 Isolation and Structural Elucidation of Naphthylisoquinoline Alkaloids from A.
tanzaniensis...............................................................................................................15
3.3.1 Extraction and Isolation............................................................................................15
3.3.2 Structural Elucidation of Ancistrotanzanine B (13)..................................................16
3.3.2.1 Spectroscopic Characterization.................................................................................16
3.3.2.2 The Absolute Configuration......................................................................................17
3.3.3 Structural Elucidation of 6-O-Methylancistrocladinine (14)....................................19
3.3.3.1 Spectroscopic Characterization.................................................................................19
3.3.3.2 The Absolute Configuration......................................................................................20
3.3.4 Structural Elucidation of Ancistrotectoriline (15).....................................................21
3.3.4.1 Spectroscopic Characterization.................................................................................21
3.3.4.2 Absolute Configuration.............................................................................................22
3.3.5 Isolation and Identification of Ancistrotanzanine C (16)..........................................23
II CONTENTS
3.3.6 Isolation and Identification of Ancistrotanzanine A (17).........................................23
3.3.7 Isolation and Identification of O,N-Dimethylancistrocladine (18)...........................23
3.4 Bioactivity Testing....................................................................................................24
3.5 Chemotaxonomic Considerations.............................................................................25
4 Isolation of Naphthylisoquinoline Alkaloids from a Congolese Ancistrocladus species
Collected in the Habitat Yeteto (Ancistrocladaceae)...........................................27
4.1 The Congolese Ancistrocladus Species....................................................................27
4.2 Isolation and Structural Elucidation of the Naphthylisoquinoline Alkaloids from the
Leaves of the Congolese Ancistrocladus Species Collected in the Habitat Yeteto..27
4.2.1 Introduction...............................................................................................................27
4.2.2 Extraction and Isolation............................................................................................27
4.2.3 Structural Elucidation of Ancistrocladinium B (22).................................................28
4.2.3.1 Spectroscopic Characterization.................................................................................29
4.2.3.2 The Absolute Configuration......................................................................................31
4.2.3.3 Kinetic Characterization of the Axial Stability of Ancistrocladinium B (22)..........34
4.2.3.4 Continuous Characterization Work...........................................................................36
4.2.4 Isolation and Characterization of Ancistrocladinium A (25)....................................37
4.3 Bioactivity of the Alkaloids......................................................................................37
4.4 Isolation and Structural Elucidation of the Naphthylisoquinoline Alkaloids from the
Roots of the Congolese Ancistrocladus Species Collected in the Habitat Yeteto....39
4.4.1 Introduction...............................................................................................................39
4.4.2 Extraction and Isolation............................................................................................39
4.4.3 Structural Elucidation of 5'-O-Demethylhamatine (26)............................................39
4.4.3.1 Spectroscopic Characterization.................................................................................39
4.4.3.2 The Absolute Configuration......................................................................................40
4.4.4 Structural Elucidation of 5'-O-Demethylhamatinine (28).........................................41
4.4.4.1 Spectroscopic Characterization.................................................................................41
CONTENTS III

4.4.4.2 The Absolute Configuration......................................................................................42
4.4.5 Structural Elucidation of 6-O-Demethylancistroealaine A (30)...............................43
4.4.5.1 Spectroscopic Characterization.................................................................................43
4.4.5.2 The Absolute Configuration......................................................................................44
4.4.6 Structural Elucidation of 6,5'-O,O-Didemethylancistroealaine A (31).....................45
4.4.6.1 Spectroscopic Characterization.................................................................................45
4.4.6.2 The Absolute Configuration......................................................................................46
4.4.7 Structural Elucidation of 5-epi-6-O-Methylancistrobertsonine A (32).....................46
4.4.7.1 Spectroscopic Characterization.................................................................................46
4.4.7.2 The Absolute Configuration......................................................................................48
4.4.8 Identification and Isolation of Known Naphthylisoquinoline Alkaloids..................49
4.5 Bioactivity of the Alkaloids......................................................................................50
4.6 Chemotaxonomic Considerations.............................................................................51
5 Isolation of Naphthylisoquinoline Alkaloids from Triphyophyllum peltatum
(Dioncophyllaceae)..................................................................................................53
5.1 Triphyophyllum peltatum..........................................................................................53
5.2 Extraction and Isolation............................................................................................53
5.2.1 Extraction by Soxhlet Apparatus..............................................................................53
5.2.2 Fast Centrifugal Partition Chromatography (FCPC).................................................54
5.2.3 Preparative HPLC.....................................................................................................56
5.2.4 Isolation from Roots of T. peltatum..........................................................................56
5.2.5 Isolation from Leaves and Twigs of T. peltatum......................................................56
6 γ-Ray Synthesis of Antiplasmodial Bioactive Naphthylisoquinoline Analogs.............58
6.1 Introduction...............................................................................................................58
6.1.1 Radiation Chemistry..................................................................................................58
6.1.1.1 Radiation Chemistry of Organic Compounds in Aqueous Solutions........................58
IV CONTENTS
6.1.1.2 γ-Ray Synthesis.........................................................................................................59
6.1.2 Strategy for γ-Ray synthesis......................................................................................59
6.2 Bioactivity Guided Isolation of γ-Ray Products.......................................................60
6.2.1 Bioactivity of Starting Material and Primary Activity Screening.............................61
6.2.2 Fractionation by FCPC and Secondary Activity Screening......................................63
6.2.3 Fractionation by HPLC and Tertiary Activity Screening.........................................64
6.2.4 Structural Elucidation of 3,4-Dihydro-1-Isoquinolinone (43).................................65
6.2.5 Structural Elucidation of 3,4-Dihydro-1-Isoquinolineamine (44)...........................66
6.2.6 Structural Elucidation of 1,2,3,4-Tetrahydro-1,2-Diazirino-Isoquinoline (45)........67
6.3 Bioactivity of the Irradiation Products 43–45...........................................................68
6.4 Evaluation of the Method..........................................................................................68
7 Antimalarial Drug–Heme Interactions............................................................................70
7.1 Introduction...............................................................................................................70
7.2 UV Titration..............................................................................................................72
7.2.1 Job's Plot...................................................................................................................75
7.2.2 Binding Constant.......................................................................................................76
7.3 Mass Spectrometry....................................................................................................78
7.4 Structural Investigations of Antimalarial Drug–FPIX Complex Formation studied by
NMR..........................................................................................................................84
7.5 β-Hematin Inhibition.................................................................................................86
8 Metabolism Study of Naphthylisoquinoline Alkaloids...................................................91
8.1 Introduction...............................................................................................................91
8.1.1 Phase 1 and Phase 2 Drug Metabolism.....................................................................91
8.1.2 In Vitro Assays for Phase 1 and Phase 2 Drug Metabolism Studies........................92
CONTENTS V

8.1.3 Metabolism of Naphthylisoquinoline Alkaloids.......................................................92
8.2 Phase 1 Metabolism Study of Dioncophyllines A (8) and C (6), and Dioncopeltine A
(7)..............................................................................................................................93
8.2.1 Liver Microsomal Incubation Assay for Phase 1 Investigations..............................93
8.2.2 Incubation of Dioncophylline A (8)..........................................................................93
8.2.3 Incubation of Dioncophylline C (6) and Dioncopeltine A (7)..................................99
8.3 Phase 2 Metabolism Study of Dioncophyllines A (8) and C (6) and Dioncopeltine A
(7)..............................................................................................................................99
8.3.1 Liver Microsomal Incubation Assay for Phase 2 Glucuronidation Investigations...99
8.3.2 HPLC-UV and HPLC-MS Analyses of the Phase 2 Glucuronidation Experiments.99
8.4 In Vivo Pharmacokinetic Profile of Dioncophylline A (8)......................................103
9 Concluding Remarks.......................................................................................................104
10 Zusammenfassung...........................................................................................................110
EXPERIMENTAL SECTION...............................................................116
1 General Aspects...............................................................................................................116
1.1 Analytical Apparatures............................................................................................116
1.2 Other Apparatures...................................................................................................117
1.3 Chromatographical Methods...................................................................................118
2 Phytochemical Investigation of Leaves from Ancistrocladus tanzaniensis.................120
2.1 Extraction and Isolation..........................................................................................120
2.2 Ancistrotanzanine B (13)........................................................................................121
2.3 6-O-Methylancistrocladinine (14)...........................................................................122
VI CONTENTS
2.4 Ancistrotectoriline (15)...........................................................................................123
2.5 Ancistrotanzanine C (16)........................................................................................124
2.6 Ancistrotanzanine A (17)........................................................................................125
2.7 O,N-Dimethylancistrocladine (18)..........................................................................126
3 Isolation of Naphthylisoquinoline Alkaloids from the Congolese Ancistrocladus
Species Collected in the Habitat Yeteto (Ancistrocladaceae)............................127
3.1 Isolation of Naphthylisoquinoline Alkaloids from the Leaves...............................127
3.1.1 Ancistrocladinium B (22)........................................................................................128
3.1.1.1 P-Ancistrocladinium B [(P)-22].............................................................................128
3.1.1.2 M-Ancistrocladinium B [(M)-22]............................................................................129
3.1.2 Ancistrocladinium A (25).......................................................................................129
3.2 Isolation of Naphthylisoquinoline Alkaloids from the Roots.................................130
3.2.1 5'-O-Demethylhamatine (26)..................................................................................131
3.2.2 5'-O-Demethylhamatinine (28)...............................................................................132
3.2.3 6-O-Demethylancistroealaine A (30)......................................................................133
3.2.4 6,5'-O,O-Didemethylancistroealaine A (31)...........................................................134
3.2.5 5-epi-6-O-Methylancistrobertsonine A (32)...........................................................135
3.2.6 Ancistroealaine A (20)............................................................................................136
3.2.7 Hamatine (27)..........................................................................................................136
3.2.8 Hamatinine (29)......................................................................................................137
3.2.9 6-O-Methylhamatinine (21)....................................................................................138
3.2.10 6-O-Demethylancistrobrevine A (34).....................................................................139
3.2.11 Ancistrocladine (35)................................................................................................140