New Natural Products, Related to Carotenoids

New Natural Products Related to Carotenoids. Tobacco continues to yield volatile constituents with carotenoid-like rings, described by some authors as nor-carotenoids . New structures reported are 5-hydroxy-5,6-dihydro-3,6-epoxy-/3-ionol [carotene numbering (19)] and the related 5,8-epoxide (20). An epoxymegastigmadiene (21) has been identified in Osmanthus absolute/ The... 

New Natural Products Related to Carotenoids Carotenoid-Protein Complexes Synthesis and Reactions Carotenoids Retinoids... 

One of the most important discoveries recently made in the field of carotenoid aroma compounds relates to the class of damascones. Seven naturally occurring members (266) to (272) of this class are known today. The discovery of these new compounds started with the isolation of damascenone (268) from Bulgarian rose oil in 1970 120). Later, the same compound was detected in various tobacco brands 5, 110, 306), tea 491), raspberry oil 708), cooked apples 442), various grape and wine varieties 546, 549), beer 598), coffee oil 179), buchu leaf oil 283) and Roman camomile 638). 3-Hydroxy-(3-damascone (269) was shown to be an important aroma component of tobacco 108, 169, 285) in which it develops a green, rose-floral and sweet Burley-like note (556). (3-Damascone (267) was found in Burley tobacco 110) and rose oil 108), whereas a-damascone (266), accompanied by (3-compound (267) and damascenone (268), was exclusively observed in tea oil 491). Among the known cyclization products (270) to (272), the last two compounds were found in tobacco (779), while ketone (270) was detected in tea 491). 

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