19 December 1952
Prof. A. R. Todd
University of Cambridge
I was pleased to learn from the New York Times that you and your group have synthesized three coenzymes. I think that this
Dr. Corey and I are much disturbed that there has been no precise structure determination reported as yet for any nucleotide.
We have decided that it is necessary that some of these structure determinations be made in our laboratory. I know that
the Cavendish people are working in this field, but it is such a big field that it cannot be expected that they will do the
whole job. On the other hand, we do not want to duplicate their investigations - it is more important that another nucleotide
determination be made, in case that they carry out one of them. Probably I shall write to Bragg or Cochran pretty soon and
ask which ones they are working on. If there is no objection on their part, we should like to ask you to provide us with
material, if you have some crystalline preparations of nucleotides or related substances that you feel would be especially
worth while investigating.
I may say that we probably shall try to determine the structure of some phosphate diester, perhaps not of the nucleotide class
- information about the structure of phosphate diesters can be carried over directly to nucleic acid.
We feel strongly the necessity of having precise information about these substances because we have, we believe, discovered
the structure of the nucleic acids. I think that it will be about a month before we send off a manuscript describing the
structure, but I have practically no doubt about the correctness of the structure that we have discovered. I feel very grateful
to you for having given me reliable information about nucleic acid, this summer. Our structure corresponds to the specifications
that you laid down; in particular it involves 3', 5' linkages between the P-ribofuranose rings, by way of phosphate groups.
The structure is really a beautiful one. It is hard to describe without some drawings, which have not yet been made. I
shall keep you informed.
I enclose a copy of a letter to Bragg, asking him for information that would keep us from duplicating work that is being done
laboratory. I may say that we have been especially interested in leaking a structure determination of ATP. We have surmised
that some unidentified crystals for which we have some x-ray data might in fact be ATP, but this has not yet been verified.
If you have any preparation of a nucleotide that is in the form of crystals, even microcrystals, and could give us a small
amount - enough to recrystallize into larger crystals - we should be happy to begin the investigation of it, provided that
it does not interfere with your collaboration with the Cavendish group.
With best wishes to you all for Christmas and the New
Year, I am