Organic Sulfur Compounds from Marine Organisms

Treasures from the Sea: Discovery and Total Synthesis of Ammosamides

“…[3] The research group of Fenical is also to be credited with the discovery of 1 and 2, which were obtained from the marine streptomyces strain CNR-698 that was isolated from oceanic bottom sediments collected at a depth of more than 1600 m. [4] Ammosamides belong to the pyrroloiminoquinone class of natural products, [5] and it is worth noting that ammosamide A (1) is the first natural product ever isolated to contain a thiog-lactam ring. [4,6] Although the structures of 1 and 2 are less complex than what one generally tends to associate with marine natural products, they still pose a formidable challenge for total synthesis, because of the dense functionalization of the aromatic core, and also because of their very poor solubility in organic solvents. [3] Hughes and Fenical have been able to meet these challenges, and the key features of their approach will be highlighted below.…”

The Ammosamides: Structures of Cell Cycle Modulators from a Marine‐Derived Streptomyces Species

“…High-resolution (ESI) mass spectrometric analysis of ammosamide A (1) indicated a molecular formula C 12 6 ]DMSO revealed six singlets between d = 6.0 and 9.0 ppm and one methyl singlet at d = 4.03 ppm, while the 13 C NMR spectra revealed the presence of eleven sp 2 hybridized carbon atoms and a single sp 3 hybridized carbon atom at d c = 33.3 ppm ( Table 1). The addition of D 2 O (20 mL) to the sample in [D 6 ]DMSO resulted in the immediate disappearance of 1 H NMR signals at d = 7.16 (1 H), 6.63 (1 H), 6.89 ppm (2 H) and the slower disappearance of singlets at d = 8.92 (1 H), and 7.68 ppm (1 H) (less than 10 min).…”

Marine isocyano compounds

“…Biological specificity is a paramount consideration if one considers two examples, Acanthella pulcherrima [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] and Pseudaxinyssa sp. .…”

“…When Acanthella acuta was reinvestigated by the same researchers, isocyano compound 20, but not acanthellin-1 (14), was found to be the 12 major isonitrile-related compound. The collection sites for both sponges were identical to those of previous studies; i.e., Axineila cannabina from the Bay of Taranto and Acanthella acuta from the Bay of Naples.…”

“…This chapter reviews the chemistry and examines the progress of naturally occurring marine isonitriles and their congeners. Several publications on the chemistry [9] and, in part, biosynthesis [10] of naturally occurring isonitriles have appeared together with specific reviews on the biosynthesis of marine isocyanoterpenoids in sponges [11] and the chemistry of organic sulfur compounds including marine isothiocyanates [12]. The progress of isocyanides and cyanides as natural products was recently surveyed [13].…”