Noun
pyranose (plural pyranoses)
(chemistry) any cyclic hemiacetal form of a monosaccharide having a six-membered ring (based on tetrahydropyran)
Conversion between the furanose, acyclic, and pyranose forms of D-glucose. Source: Internet
Four isomers are cyclic, two of them with a pyranose (six-membered) ring, two with a furanose (five-membered) ring. Source: Internet