The present invention relates to compound of formula (I) or a stereoisomer thereof, in particular amarouciaxanthin A acetate. The invention also relates to the method of preparation of these compounds, to compositions comprising them as well as their medical and cosmetic uses.

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The present invention relates to compound of formula (I) or a stereoisomer thereof, in particular amarouciaxanthin A acetate. The invention also relates to the method of preparation of these compounds, to compositions comprising them as well as their medical and cosmetic uses. ##STR00001##

The present invention relates to compound of formula (I) or a stereoisomer thereof, in particular amarouciaxanthin A acetate. The invention also relates to the method of preparation of these compounds, to compositions comprising them as well as their medical and cosmetic uses. ##STR00001##

New plant growth regulators, including compounds and compositions, and methods of use including for promoting root growth. The compounds are carotenoid oxidation products, and a preferred example is 3-OH--apo-13-Carotenone. A method comprising promoting the growth of at least one plant with use of an effective amount of at least one composition comprising an effective amount of at least one compound which is represented by A-B-C, wherein B is a bivalent polyene moiety, A is a monovalent moiety linked to B by a six-membered carbon ring, wherein the ring has at least one substituent linked to the ring by an oxygen atom, and C is a monovalent moiety linked to B by a carbonyl group. Synergistic effects can be used with combinations of compounds.

New plant growth regulators, including compounds and compositions, and methods of use including for promoting root growth. The compounds are carotenoid oxidation products, and a preferred example is 3-OH--apo-13-Carotenone. A method comprising promoting the growth of at least one plant with use of an effective amount of at least one composition comprising an effective amount of at least one compound which is represented by A-B-C, wherein B is a bivalent polyene moiety, A is a monovalent moiety linked to B by a six-membered carbon ring, wherein the ring has at least one substituent linked to the ring by an oxygen atom, and C is a monovalent moiety linked to B by a carbonyl group. Synergistic effects can be used with combinations of compounds.