Abstract:

On the basis of Kier s molecular connectivity index (mXtV) and electronegativity distance vector (Md), the retention time of 20 organic components in volatile oil from Rhoeo spathacea (Sw.) Stearn flowers was determined and a four-variable model (QSRR) of gas chromatographic retention time (tR/min) for 20 chemical components was established from mXtV, Md by leaps-andbounds regression (LBR). Traditional correlation coefficient (R) and cross-validation correlation coefficient (Q) of leave-one-out (LOO) were 0.963 and 0.832, respectively. The model was highly reliable and had favorable prediction capability. The dominant factors for retention time were molecular size and spatial shape of organic molecules. The Kier s converse indices and electronegativity distance vector exhibited a good rationality and efficiency in characterizing retention time of organic compounds. This model could elucidate the change trend of retention indices for organic components.

Key words: Rhoeo spathacea (Sw.) Stearn, gas chromatographic retention time, connectivity index, electronegativity distance vector, quantitative structure-retention relationship (QSRR)