six-carbon

D-Sorbitol (Sorbitol) is a polyhydric alcohol with about half the sweetness of sucrose, occurring naturally and also produced synthetically from glucose. Formerly used as a diuretic, it may still be used as a laxative and in irrigating solutions for certain surgical procedures. It is also utilized in various manufacturing processes, as a pharmaceutical aid, and in several research applications.

Pyrimidine (Metadiazine)s are heterocyclic, six-membered, nitrogen-containing carbon ring structures, with uracil, cytosine and thymine being the basal structures of ribose-containing nucleosides (uridine, cytidine, and thymidine respectively), or deoxyribose-containing deoxynucleosides, and their corresponding ribonucleotides or deoxyribonucleotides. Pyrimidines serve essential functions in human metabolism as ribonucleotide bases in RNA (uracil and cytosine), and as deoxyribonucleotide bases in DNA (cytosine and thymine), and are linked by phosphodiester bridges to purine nucleotides in double-stranded DNA, in both the nucleus and the mitochondria. Pyrimidine activated sugars are also involved in polysaccharide and phospholipid synthesis, glucuronidation in detoxification processes, glycosylation of proteins and lipids and in the recently identified novel endothelium-derived vasoactive dinucleotides.

α-L-fucopyranose, an endogenous metabolite and six-carbon deoxyhexose, is present at the terminal or anterior position of many cell surface oligosaccharide ligands, mediates cell recognition and adhesion signaling pathways, and is a potentially critical molecule in pathological processes, including tumors.

Depudecin is a polyketide obtained from the fungus Alternaria brassicicola and having a highly unusual structure of an 11-carbon chain containing two epoxides and six stereogenic centres. It is an inhibitor of histone deacetylase (HDAC) both in vivo and in vitro and also exhibits anti-angiogenic activity.