1. A prefix which indicates a shift by one position of all single and double bonds in a conjugated polyene system. It has been applied only to carotenoids and retinoids, e.g. retro-carotenoids, retro-retinoids.
  2. A prefix which indicates the reverse sequence of a peptide.
PAC, 1995, 67, 1307 (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1363
Blue Book (Guide), p. 32
See also:
White Book, p. 229
White Book, p. 249
White Book, p. 64