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Showing 1 - 5 of 5 matches in All Departments
1. B.J. Baker, R.G. Kerr: Biosynthesis of Marine Sterols 2. C.W.J. Chang, P.J. Scheuer: Marine Isocyano Compounds 3. G. Cimino, G. Sodano: Biosynthesis of Secondary Metabolites in Marine Molluscs 4. W.H. Gerwick, D.G. Nagle, P.J. Proteau: Oxylipins from Marine Invertebrates
Since the late 1950's when proton n. m. r. spectroscopy was first used in organic natural products studies the technique has increasingly con of this important area of chemistry. tributed to the rapid advancement Although the potential utility of 13C n. m. r. was recognized very early, essentially no application of 13C n. m. r. appeared in the literature prior to 1966 and 95% of the existing data are less than five years old. The initially slow growth had its cause in inadequate instrumentation, insufficient sensitivity being the main obstacle. This situation drastically changed with the advent and commercial availability of broadband ex citation and Fourier transform methods, giving natural-abundance 13C n. m. r. and its numerous chemical applications a tremendous impetus. Today BC spectra can be recorded on sample quantities down to the submilligram level, which until recently even withstood proton n. m. r. Paralleling the development of experimental techniques considerable progress has also been made on an understanding of spectral parameters, in particular their stereochemical implications on natural products. Although the large majority of data present up to now deals with known structures, an adequate basis now exists which allows the chemist to use the technique for tackling real problems on unknown molecules."
Glycosmis is a clearly defined genus within the tribe Clauseneae of the Aurantioideae subfamily of the family Rutaceae comprising about 40 species (1). Its range of distribution is centered in south and southeast Asia (India, Sri Lanka, Myanmar, Thailand, Malaysia, Indonesia) and extends to south China and Taiwan as well as to New Guinea and north Australia. Exceptions are only cultivated species like the Chinese G. parvijiora (Sims) Little, formerly called G. citrifolia (Willd. ) Lindley, which became naturalized in tropical America and Africa (Angola) (1). The shrubs or small trees are unarmed and possess pinnate or simple leaves with translucent punctate glands emitting an aromatic odor when crushed. The axillary inflorescences are usually dispersed closed panicles with small white flowers. The fruits are mostly pink, reddish or white berries of about I cm in diameter with only one or two seeds. The genus name Glycosmis originates from the sweet smell of the flowers and the sweet taste of the fleshy pericarp of the fruits. A good field and herbarium character of the genus is that the buds of new leaves are usually covered with short rusty-red hairs. In spite of the good delimitation of Glycosmis from the other closely related Clauseneae genera Clausena, Micromelum, Murraya, and Merrillia and the already existing subrevisionary treatment by Stone (1), there are still many unresolved taxonomic problems at the species level.
Since the late 1950's when proton n. m. r. spectroscopy was first used in organic natural products studies the technique has increasingly con of this important area of chemistry. tributed to the rapid advancement Although the potential utility of 13C n. m. r. was recognized very early, essentially no application of 13C n. m. r. appeared in the literature prior to 1966 and 95% of the existing data are less than five years old. The initially slow growth had its cause in inadequate instrumentation, insufficient sensitivity being the main obstacle. This situation drastically changed with the advent and commercial availability of broadband ex citation and Fourier transform methods, giving natural-abundance 13C n. m. r. and its numerous chemical applications a tremendous impetus. Today BC spectra can be recorded on sample quantities down to the submilligram level, which until recently even withstood proton n. m. r. Paralleling the development of experimental techniques considerable progress has also been made on an understanding of spectral parameters, in particular their stereochemical implications on natural products. Although the large majority of data present up to now deals with known structures, an adequate basis now exists which allows the chemist to use the technique for tackling real problems on unknown molecules."
The volumes of this classic series, now referred to simply as Zechmeister after its founder, L. Zechmeister, have appeared under the Springer Imprint ever since the series inauguration in 1938. The volumes contain contributions on various topics related to the origin, distribution, chemistry, synthesis, biochemistry, function or use of various classes of naturally occurring substances ranging from small molecules to biopolymers. Each contribution is written by a recognized authority in his field and provides a comprehensive and up-to-date review of the topic in question. Addressed to biologists, technologists, and chemists alike, the series can be used by the expert as a source of information and literature citations and by the non-expert as a means of orientation in a rapidly developing discipline.
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