Charles C. Price

Relative reactivities for monofunctional nitrogen mustard alkylation of nucleic acid components

Abstract Quantitative studies of alkylation of nucleic acid bases have led to values for relative nucleophilicities of their reactive centers toward the diethylethylenimonium ion. The alkylation of native, double-helix DNA by diethylethylenimonium ion for 2 h at 40° and pH 7, followed by hydrolysis, dialysis and chromatography, showed only 7-alkylated guanine. After 48 h, considerable N 6 -alkylated adenine was also obtained. Since complete denaturation and extensive degradation of DNA occurred under the latter conditions, initially denatured DNA was alkylated for 2 h and found to give about equal amounts of both compounds. The alkylation of guanine in native DNA proceeded at a rate 50-fold greater and in denatured DNA at a rate 7-fold greater than in monomeric guanine ribosides and ribotides. While adenine units in native DNA are unreactive, in denatured DNA they react at a rate 5 times those in poly A.

MECHANISM OF ACTION OF ALKYLATING AGENTS

In the last decade, since a summary on this topic was presented at an earlier symposium,’ an impressive array of data has accumulated on the importance and nature of attack of alkylating agents on DNA, RNA, and their constituent^.^-^^ Most of the alkylating agents responsible for the biological interest in this class of chemical reagents proceed through a common mechanism, involving secondorder nucleophilic substitution (&):

Stereochemical factors in epoxide polymerization by base and coordination catalysts

Abstract The amorphous fraction accompanying isotactic poly (propy-lene oxide) or poly(tert-butylethylene oxide) formed by co-ordination catalysts was shown by degradation to the dimer glycols to involve inversion of configuration at every ring opening at the secondary carbon atom for (R) - [or (S) -] PO and to involve no stereoselection in the coordination step for tert-BuEO. The crystalline poly(tert-BuEO) formed by polymerization with tert-BuOK was similarly shown to give equal amounts of erythro and threo dimer glycol. It is proposed that these dimer units arise from regular alternate isotactic and syndiotactic placements (iso,syn). Aryl glycidyl

Some Social and Philosophical Implications of Progress on the Origin and Synthesis of Life

There has been remarkable progress in synthesizing more complex essential components of living organisms and of obtaining ever greater understanding of the processes by which life may have originated on this planet. These developments will have significant practical consequences, but perhaps as important will be some of the implications they provide for the philosophical view of man--what he is, where he came from, where he may be headed.

Selectivity in Addition Polymerization

The development of methods to control selectivity in polymerization processes has been a major accomplishment of polymer chemists during the past quarter of a century. Despite the immense amount of industrial and academic effort expended, and despite much broad understanding of the factors involved, a full understanding of much of the detail of many aspects of selectivity in polymerization remains as a challenge to chemists.

Political Action for a Livable World

“While most responsible Americans can be motivated to work on ecology problems, the population explosion or the energy crisis, the general attitude seems to be to leave the nuclear war problem to the military.” Charles C. Price urges here that once again the U.S. government assume an active role in seeking a comprehensive approach to genuine and complete disarmament by establishing a top-level civilian effort with this responsibility. Dr. Price, past president of the American Chemical Society and the Federation of American Scientists, is now professor of chemistry at the University of Pennsylvania, board chairman of the Council for a Livable World and president of the World Federalists Education Fund. He delivered this address on the occasion of his receiving the 1973 American Chemical Societys Charles Lathrop Parsons Award for outstanding public service.