SummaryThree diols, 2-methylidene-l , 3-propanediol, 2-methyl-l , 3-propanediol and 1,3-butanediol, esterified on one hydroxyl group with isobutyric acid and on the other with angelic acid'), have been isolated from Anthemis nobilis oil (Roman camomile) and synthesized. The presence of homologous esters is very probable.In previous publications [ 11 [ 2 ] , we presented some of our results on the analysis of the oil of Roman camomile (Anthemis nobilis). We now describe the isolation and synthesis of three diesters 1-3 (R' = angelyl'), R2 = (CH3),CHCO), and suggest that other similar esters are present, notably the homologue 1, with R' = angelyl and R2= CH3CH2CH(CH3)C0. These esters contribute to the odour of the oil.Work-up of the oil was described in the foregoing publication [2], and the diesters now described occurred in the fraction which was slightly more polar than the one containing the unsaturated ketones discussed there. All these compounds have approximately the same volatility, and 1-3 (R' = angelyl, R2= (CH3)2CHCO) were eluted in that order from a Carbowax gas chromatography (GC.) column.Clearly 1 and 2 are chiral (when R' and R2 are different in the case of 2), and sufficient of 1 (R' = angelyl, R2= (CH&CHCO) was available to show that the natural product was laevorotatory. The identification of all the esters was by 'H-NMR. and i i i , r \ \ spectrometn (MS.; see exper. part). In the 360-MHz-'H-NMR. spectrum of 3 (R' = angelyl, R2= (CH,),CHCO) a doublet at 1.27 ppm was observed indicating the presence of an impurity. This doublet is at the same position as that of the methyl group in the butanediol part of 1 (R'= angelyl, R2= (CH&CHCO). In this impurity there appeared to be another methyl group giving rise to a triplet at 0.90, and we suggest that the presence of the homologue 1 (R'=angelyl,