Bioorganic Marine Chemistry

The present series, "Bio-organic Marine Chemistry," is being launched at a time when we have the fundamental knowledge and the requisite instrumentation to probe the molecular basis of many biological phenomena. The final volume of "Marine Natural Products-Chemical and Biological Perspectives" (Academic Press), which may be con sidered the precursor of this series, was published in 1983. In that series, which I edited, primary emphasis was placed on molecular structure and phyletic relationships. This focus was compatible with the major concerns of a growing research community in the field of marine natural products. Moreover, a need existed for timely reviews of a rapidly expanding and widely scattered primary literature. As I read again the Preface to Volume 1 (1978), I am amazed at the changes in direction and emphasis which have taken place during these few intervening years. Sufficient basic data are now at hand to gauge the breadth of the marine natural product spectrum and to raise questions of functions, both within and outside the marine ecosystem. Although we have few answers, the questions have become meaningful and pointed. Furthermore, the task of tracking and cataloguing the steady stream of fascinating new structures has been assumed by Faulkner's periodic surveys in Natural Product Reports, a bimonthly publication of the Royal Society of Chemistry. The study of marine natural products remains firmly anchored in chemistry, i. e. in molecular integrity, yet continues to seek greater involvement in functional biology.

Burgeoning research into marine natural products during the past two decades has in no small measure been due to an heightened and world-wide interest in the ocean, to the development of new sophisticated computer-driven instrumentation, and to major advances in separation science. Organic chemists have been fully aware that processes in living systems occur in an aqueous medium. Nevertheless, the chemists who have specialized in the study of small molecules have found it expedient to use organic rather than aqueous solvents for the isolation and manipulation of secondary metabolites. The emergence of new chromatographic techniques, the promise of rewarding results, not to mention the relevance of polar molecules to life itself, have contributed to a new awareness of the importance of organic chemistry in an aqueous medium. The first chapter in Volume 2 of Bioorganic Marine Chemistry reflects the growing interest and concern with water-soluble com pounds. Quinn, who pioneered the separation of such molecules, has contributed a review which closely links techniques with results and is based on practical experience. The second chapter, by Stonik and Elyakov, examines the vast chemical literature of the phylum Echinodermata - over one fourth of it in difficulty accessible Russian language publications. The Soviet authors evaluate the data for their suitability as chemotaxonomic markers.

The first three chapters of Vol. 3 of Bio-organic Marine Chemistry deal with the chemistry and function of peptides. Chapter 1 by Ireland and coworkers serves as an introduction to marine-derived peptides. It is arranged phyletically and encompasses the entire range from dipeptides to a compound with 95 amino acid residues. Peptides involved in primary metabolism and hence belonging to the realm of macromolecular biochemistry are excluded. However, it might be mentioned in passing that the dividing line between large and small molecule chemistry is continually becoming less distinct. Not only are more compounds of intermediate size, from 1,000 to 10,000 dalton, being discovered, but instruments and techniques, particularly in mass spectrometry and nuclear magnetic resonance have been developed for their structural elucidation by what is considered small molecule methodology. Two groups of peptides are discussed in separate chapters. Biologists who have observed and described the mating behavior of diverse species of marine invertebrates have long surmised that a chemical mechanism might be operating in many cases of individual as well as mass fertilization. The chemical activators of sea urchin sperm prove to be a series of peptides, whose structures and activity are discussed by Suzuki.

Volumes five and six of Bioorganic Marine Chemistry differ from their predecessors in two respects - they deal exclusively with laboratory synthesis of marine natural products and they represent the effort of a single author and his associates. The rationale for these departures is readily perceived. For several decades organic synthesis has without doubt been the most spectacular branch of organic chemistry. While the late R.B. Woodward's dictum - organic compounds can undergo only four basic reactions: they can gain electrons; they can lose electrons; they can be transformed with acid or with base - is still true, the wealth and variety of available reagents which will accomplish chemical transformations has reached staggering proportions. Little wonder then, that synthetic methodology has achieved a high degree of predictability and total synthesis of natural products has been successfully directed toward ever more challenging targets. As for the second point, that of single authorship, multiple authorship would invariably have led to gaps and overlaps, thus making it difficult to assemble and assess recent research in a systematic and comprehens ive fashion.

Burgeoning research into marine natural products during the past two decades has in no small measure been due to an heightened and world-wide interest in the ocean, to the development of new sophisticated computer-driven instrumentation, and to major advances in separation science. Organic chemists have been fully aware that processes in living systems occur in an aqueous medium. Nevertheless, the chemists who have specialized in the study of small molecules have found it expedient to use organic rather than aqueous solvents for the isolation and manipulation of secondary metabolites. The emergence of new chromatographic techniques, the promise of rewarding results, not to mention the relevance of polar molecules to life itself, have contributed to a new awareness of the importance of organic chemistry in an aqueous medium. The first chapter in Volume 2 of Bioorganic Marine Chemistry reflects the growing interest and concern with water-soluble com pounds. Quinn, who pioneered the separation of such molecules, has contributed a review which closely links techniques with results and is based on practical experience. The second chapter, by Stonik and Elyakov, examines the vast chemical literature of the phylum Echinodermata - over one fourth of it in difficulty accessible Russian language publications. The Soviet authors evaluate the data for their suitability as chemotaxonomic markers.