2nd Edition
Chemistry of Natural Products A Unified Approach, Second Edition
The second edition of a bestseller, this book discusses the common structural and stereochemical features of naturally occurring organic compounds. It includes a variety of examples to illustrate varied aspects so that the range of structure and behavior exhibited by these compounds is retained within the set framework. The author explores the increasing application of physical (spectroscopic) methods like IR, NMR, CD, ORD, MS, High Resolution Mass Spectroscopy without undermining the importance of ‘classical’ chemical methods. The section on problem solving helps to develop an analytical and critical evaluation of the data.
Introduction
The terpenes
The alkaloids
Flavonoids and related compounds
Xanthones
Other oxygen heterocyclic compounds
Quinonoid compounds
Lichen metabolites
Concluding remarks
Structure
Introduction: A survey of the methods used for determination of structures
Strychnine: A hard nut to crack!
Nepitrin and pedaliin: A case of mistaken identity!
Colchicine: Structure from ‘armchair’ research!
Longifolene: A molecular acrobat!
ß-amyrin: A ‘straight’ molecule
Wedelolactone: Th e first of the coumestans
Protoaphin-fb : An insect pigment
Tylophorine: Another ‘straight’ molecule with a kink or two!
Heliangine: An anti-auxin
Delphisine: Confi rmation of a structure by NMR spectra
Tubocurarine: Th e sting in the arrow
Sclerophytins A and B: Cytotoxic diterpenes from marine coral
Mangiferin: Parent of the Indian yellow
Conessine: A pseudo alkaloid
Stereochemistry
Introduction
Absolute stereochemistry of morphine
Quinine and related alkaloids
Emetine
Enhydrin
Conformations of naturally occurring germacranolides
Stereochemistry of rotenoids
Lactone fusion in sesquiterpene lactones
Stereochemistry of abietic acid
Catechins
Sphingosine
Stereochemistry of menthol
Stereochemistry of the kamahines
Absolute confi guration of benzyl isoquinoline alkaloids
Stereochemistry of some indole alkaloids
Reactions and Rearrangements
Introduction
Rearrangement reactions of morphine
Smaller and more agile molecular acrobats
The Wesley–Moser rearrangement
Some interesting reactions of reserpine
Molecular yoga: Reactions of papaverine
Two examples of transannular reactions
The epoxide as a medium of articulation
Capillarisin: An example of SN2 displacement
The reverse of a transannular cyclisation
The epoxide group as a ‘handle’ for conversion
Reactions of linalool
The Nametkin rearrangement
Reactions of caryophyllene
Santonin to desmotroposantonin: An example of dienone–phenol rearrangement
Synthesis
Introduction
Synthesis of polyoxygenated fl avones with uncommon oxygenation patterns
Two contrasting syntheses of anthracyclinones
An approach to quassinoid synthesis
Synthesis of a semiochemical
A synthesis of polygodial
Balsamiferone and gravelliferone
Gyrinal: Defensive secretion of an insect
Synthesis of an unusual methylthiophenanthrene diol
A synthesis of (-) khusimone
Synthesis of a chiral marine natural product
A biomimetic synthesis of morphine
Synthesis of ergocristine
A stereoselective synthesis of reserpine
Synthesis of a paraconic acid
Biosynthesis
Introduction
Biosynthesis of some benzylisoquinoline alkaloids
Reticuline to morphine
From phenylalanine to colchicine
Tryptophan to quinine
Biosynthesis of some indole alkaloids
Biosynthesis of ergot alkaloids
Evolution of the monoterpenes
From mevalonic acid to the sesquiterpenes
Biosynthesis of some diterpenes
A brief note on the biosynthesis of ophiobolins
Geranyl pyrophosphate to lanosterol and the triterpenes
Non-nitrogenous secondary metabolites from shikimic acid: Flavonoids and related polyphenols
Biosynthesis and transformations of isofl avones
Biosynthesis of anthraquinones
Biological Significance of Secondary Metabolites
Introduction
Semiochemicals: An overview
Insect pheromones
Plant–insect interactions
Plant–vertebrate interactions
Plant–plant interactions
Plant–microbe interactions
Phytoalexins
Insect–animal interactions
Defensive secretions of insects
Problems
Index
Biography
Dr N R Krishnaswamy has over 30 years of teaching experience in institutions such as the All India Institute of Medical Sciences, New Delhi, University of Delhi, Bangalore University, Calicut University and Sri Sathya Sai Institute of Higher Learning, where he was Professor and Head, Department of Chemistry.