Electron Spin-Echo Envelope Modulation
epithelium and thereby regulate the metabolism and rate of turnover of the primary olfactory neurons in which this dipeptide is synthesizeda6 We feel we must stress that the experiments presented here and elsewhere1'J"17 do not answer the question of what effect rapid intramolecular vibration and bending might have on the magnetic coupling of the two copper(I1) ions in a molecule such as that in Figure 1 (IV). Although we can state that a monomeric copper(I1) complex is in dynamic chemical equilibrium with the dimeric complex, it is not readily apparent what portion of the enhanced signal amplitude of the ESR spectrum at elevated temperatures (Figure 6) arises from a shift in the chemical equilibrium and what portion might arise from increased intramolecular motion of the dimeric complex.
Acknowledgment. We thank the Biomedical ESR Center for the use of the ESR spectrometer and Dr. Jacob Ghazarian and Dr. Henry Miziorko for use of the UVvisible absorption spectrophotometers. This investigation was supported by a Biomedical Research Support Grant from The Medical College of Wisconsin, NIH Grant CA 20737, and NIH Grant RR-01008.
References and Notes (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (1 1) (12) (13) (14)
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