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The H spin-lattice relaxation times of the proton-bearing groups and the P spin-lattice relaxation times in C-phosphorylated oximes RC(=NOH)P(=O)RR (R = Ph, R = R = OMe; R = Ph, R = OMe, R = OCHCHBr; R = PhCH, R = R = OCHMe) and dioxime RP(=O)C(=NOH)(CH)C(=NOH)P(=O)R (R = OMe) in DMSO-d were measured. The characteristic reorientation times of the whole molecules were estimated using the measured values of the H relaxation times and the results of semiempirical PM3 quantum chemical calculations of the molecular geometries. The reorientation times were used to identify the contributions of different relaxation mechanisms to the rate of P spin-lattice relaxation. The anisotropy of the chemical shielding of P nuclei was evaluated from the difference between the P relaxation rates measured at 101.27 and 161.92 MHz. [ABSTRACT FROM AUTHOR]