Identification of the C10 aldehyde derivative of limonene in the volatile oil of dracocephalum kotschyi boiss. using 2D-NMR

GC-MS analysis of the volatile oil, extracted by hydro-distillation from dried aerial parts of Dracocephalum kotschyi, revealed that the major constituents were geranial [35.8%], C 10H14O [26.6%], limonene [15.8%] and 1, 1-dimethoxy decane [14.5%]. In order to isolate the unknown oxygenated monoterpene, fractionation of the volatile oil was carried out on silica gel column chromatography. The structures of the separated compounds were confirmed to be geranial, neral and limonene-10-al [C 10H14O] by analysis of physical and spectroscopic data [[1]H NMR, [13]C NMR, HMBC and HMQC experiments]