D-Tagatose a rare natural hexoketose is an isomer of d-galactose. D-Tagatose occurs naturally in Sterculia setigera gum and it is also found in small quantities in various foods such as sterilized and powdered cow's milk hot cocoa and a variety of cheeses yogurts and other dairy products.

D-chiro-Inositol is an epimer of myo-inositol that is found in certain mammalian glycosylphosphatidylinositol protein anchors and inositol phosphoglycans possessing insulin-like bioactivity.

Homocystine is the double-bonded form of homocysteine but it occurs only transiently before being converted to the harmless cystathionine via a vitamin B6-dependent enzyme. Increasing evidence supports a role for an elevation of homocysteine in schizophrenia.