RXMARINE CHEMICAL TAG::
Cytosine consists of a heterocyclic aromatic ring, an amine group at C4, and a keto group at C2. Cytosine binds with ribose to form the nucleoside cytidine and with deoxyribose to form deoxycytidine. The molecule is of planar geometry and cytosine forms 3 hydrogen bonds with Guanine in the DNA double helix.
doses of 3 to 50 mg./Kg. given at varying intervals, cytosine arabinoside induced definite megaloblastic changes in the marrow of all patients.