Temperature and field dependent 1H-NMR relaxation data as probes of prostaglandin motional parameters in aqueous media.
Proton resonance correlation times (tau eff) for PGF2 alpha and a more rigid analog have been derived from the field-strength dependence of spin-lattice relaxation times ( T1D ) using 200 and 500 MHz observation. Those hydrogens showing tau eff less than the value calculated for whole molecule tumbling (which applies for H-5----H-15) also show a significantly greater temperature dependence for T1D at 500 MHz. Minor wagging may occur at the C-7 and C-10 methylenes , and gradually increasing segmental motion is observed toward both side chain termini. A current model for the aqueous geometry of PGF2 alpha is developed from this data and studies of relaxation rate changes upon specific deuteration.
D055598:Chemical Phenomena; D002621:Chemistry; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D011460:Prostaglandins F / Q000032:analysis*; D012996:Solutions; D013696:Temperature
D011460:Prostaglandins F; D012996:Solutions