The main constituent of bone and teeth.[image].can be prepared not only with sodium phosphate as previously shown but with glucose-phosphoric acid or the phosphoric acid obtained therefrom by enzyme cleavage, if the synthesis is carried on at 38-40[degree]. A glycine derivative of this compound was prepared and in addition the glycine-hexol salt.[image].Both syntheses are best performed if natural ice water containing a P compound is used. These glycine derivatives are relatively stable and this is taken as evidence in favor of the assumption that the organic matter of bone and teeth is in chemical combination with phos-phato-calcium carbonate.