This study includes: (1) An evaluation of cyclic enediol pyrophosphates, and related reagents, for the synthesis of ribo- and deoxyribo-oligonucleotides, with emphasis on guanosine derivatives (GpG, etc.), in the sequence of tRNA's. (2) A study of the effect of Mg2 positive ions on the structure and conformation of (a) oligonucleotides; (b) tRNA and DNA tertiary structure. (3) A study of new methods of synthesis of divalent metal salts of oligonucleotides in anhydrous or low hydration state in order to introduce into the salts known amounts of additional ligands to complete the Mg2 positive coordination sphere in well defined metal oligonucleotide complexes.