• Vitamin B13: orotic acid, now known not to be a vitamin.
  • Vitamin B14: cell proliferant, anti-anemia, rat growth, and antitumor pterin phosphate named by Earl R. Norris. Isolated from human urine at 0.33ppm (later in blood), but later abandoned by him as further evidence did not confirm this. He also claimed this was not xanthopterin.
  • Vitamin B15: pangamic acid
  • Vitamin B16: dimethylglycine (DMG)