Cardiac Glycosides
Steroidal cardiac glycosides (1 ) constitute a fascinating series of plant natural products (2 , 3 ) some of whose representatives are important clinical agents (4 ). They comprise one of the most interesting medicinally efficacious groups of naturally oc
- PDF / 4,547,290 Bytes
- 85 Pages / 439.37 x 666.14 pts Page_size
- 15 Downloads / 187 Views
Contents 1. Introduction
71
2. Isolation and Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1. Structural Features of Cardiac Genins . . . . . . . . . . . . . . . . . . . . . , 2.2. Sugars of Cardiac Glycosides . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3. Sequence, Number and Identification of Monosaccharides. . . . . . . . . .. 2.4. I.R. Spectroscopy of Cardiac Glycosides . . . . . . . . . . . . . . . . . . . .. 2.5. Mass Spectrometry of Cardiac Glycosides . . . . . . . . . . . . . . . . . . .. 2.6. NMR Spectrometry of Cardiac Glycosides . . . . . . . . . . . . . . . . . . .
72 73 74 75 75 75 76
3. Biological Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
78
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
79
Table 1. Cardenolide Glycosides Isolated from Plants. . . . . . . . . . . . . . . . .. Table 2. Bufadienolide Glycosides Isolated from Plants. . . . . . . . . . . . . . .. Table 3. Formulas of Cardiac Glycosides . . . . . . . . . . . . . . . . . . . . . . ..
79 106 109
References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
148
1. Introduction Steroidal cardiac glycosides (1) constitute a fascinating series of plant natural products (2, 3), some of whose representatives are important clinical agents (4). They comprise one of the most interesting medicinally efficacious groups of naturally occurring substances and are widely used to influence the vital blood pumping mechanism. W. Herz et al. (eds.), Progress in the Chemistry of Organic Natural Products © Springer-Verlag/Wien 1996
72
D. DEEPAK, S. SRIVASTAVA,
N. K.
KHARE,
and A.
KHARE
o
HO
HO
Bufadienotide
Cardenolide Fig. 1
Isolation of these glycosides has been reported from more than ten dozen species belonging to ten different plant families (5, 6). They are found in almost every plant part but occur primarily in the seeds, the amount depending on maturity, time of collection and plant origin (1). They are steroidal glycosides with an ()(,~-unsaturated lactone ring attached to C-17 of the perhydrocyclopen-tanophenanthrene nucleus, the sugar being attached to the aglycone by an acetal linkage. The nature of the aglycone part leads to their classification into two different groups, the cardenolides and the bufadienolides (Fig. 1). Those aglycones containing 23 carbons with a five membered ()(,~-unsaturated y-lactone are known as cardenolides (7), whereas those with a doubly unsaturated six membered lactone (()(-pyrone) ring attached to C-17 of the steroidal moiety constitute the bufadienolides (2). Some cardiac glycosides are used successfully as heart stimulating drugs (4,8). The literature discloses that the cardenolides are more useful therapeutic agents than the bufadienolides (1). Several review articles dealing with different aspects of the cardiac glycosides exist (58, 59, 60). A comprehensive review by RASTOGI et al. (1) covered the literature till 1967. The present
Data Loading...
