The chemistry and biology of guanidine natural products

Abstract

Covering: 2015 and 2016The chemistry and biology of natural guanidines isolated from microbial culture media, from marine invertebrates, as well as from terrestrial plants and animals, are reviewed. Emphasis is directed to the biosynthesis, total synthesis, ecological roles as well as on the evolution of guanidines isolated from natural sources.

Enzymes that detoxify marine toxins

“…This strongly suggests that sulfo groups reduce PST toxi city, further highlighting their potential for incorporation into PSTbased drug candidates. The use of biosynthetic enzymes to modify PSTs represents a strategy that is distinct from the chemicalsynthesis approaches more frequently used to make analogues of these natural products 12 . Although many of those synthetic efforts have been successful, they often involve long sequences of reactions and deliver low yields of products as a con sequence of the challenging architectures of the PSTs -which contain an abundance of reactive oxygen and nitrogen atoms that com plicate the use of morestandard chemical reactions.…”

Synthetic Approaches to a Challenging and Unusual Structure—An Amino-Pyrrolidine Guanine Core

“…About one-third of all approved drugs classified as "small molecules" in this period are natural products, derived from natural or synthetic products but with a natural pharmacophore. Guanidine derivatives can be found in several natural products from diverse origin [9,10] and this structural unit is present as a building block in various pharmaceuticals such as rosuvastatin a cholesterol biosynthesis inhibitor, [11] guanabenz used clinically as an antihypertensive agent, [12] imatinib a tyrosine kinase inhibitor [13] used as an anticancer drug and the blockbuster drug used to treat peptic ulcers and cimetidine a histamine H2 receptor antagonist that inhibits stomach acid production [14]. Considered to be one of the strongest organic bases (pK HA = 13.6) guanidine has the capacity to bind to carboxylates, phosphates and metals with the guanidinium cation engaging special interactions between ligand/receptor or enzyme/substrate [15].…”

Photosynthetic production of the nitrogen-rich compound guanidine

“…It serves as a prominent functional group in essential metabolites including arginine, creatine, guanine, as well as in a wide range of secondary metabolites. 2 Due to its high pK a (13.6), it is a strong base and is positively charged under physiological conditions. Many of its applications are related to this unique property.…”