Microbial metabolites containing nitrogen

Among the alkaloids, the most unusual example is an acaricidal (lethal to arachnids) monot-erpene derivative, altemicidin (Structure 18.3). This novel alkaloid was purified from amarine strain of Streptomyces sioyaensis SA-1758 isolated from marine sediments collected from the northern part of Japan. It yielded potent antitumor activity in vitro against L1210 murine leukemia and IMC carcinoma cell lines, but was toxic in vivo in mice. Altemicidin is a novel sulfur- and nitrogen-containing microbial metabolite with a monoterpene carbon skeleton.12... 

Alkaloids represent one of the largest class of natural products with over 12000 defined structures [1], They can be summarized as nitrogen containing, mostly N-heterocyclic substances whose carbon skeleton is derived from amino acids. In a broader definition this group includes proto- and pseudoalkaloids and a number of microbial metabolites that are usually classified as antibiotics. In this review a broad definition of what to consider an alkaloid was chosen, albeit the emphasis is on alkaloids sensu strictu. 

Alkaloids are a naturally occurring large group of pharmacologically active nitrogen-containing secondary metabolites of plants, microbial or animal... 

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