Vitamin B9, molecular model. The chemical formula for vitamin B9, also called folic acid or folate, is C19.H19.N7.O6. Atoms are represented as rods and are colour-coded: carbon (blue), hydrogen (gold), nitrogen (dark blue) and oxygen (red). Vitamin B9 is most concentrated in leafy vegetables such as spinach, legumes, seeds and other fruit and vegetables. It is required for foetal development in pregnancy. It also ensures normal red blood cell formation and helps to maintain a healthy central nervous system. Folate deficiency can lead to the development of forms of anaemia and leukaemia.