BRASSINOSTEROIDES, PROCEDE POUR LES PREPARER, AINSI QUE PRODUITS CONTENANT DE TELS COMPOSES ET AYANT UNE ACTION REGULATRICE SUR LA CROISSANCE DES PLANTES

L'INVENTION CONCERNE DE NOUVEAUX BRASSINOSTEROIDES. ILS REPONDENT A LA FORMULE:(CF DESSIN DANS BOPI)DANS LAQUELLE R REPRESENTE UN RADICAL ALKYLE OU ALCENYLE, Z REPRESENTE UN RADICAL -CO-O-CH- CO-CH-, ET R ET R SONT DIFFERENTS L'UN DE L'AUTRE ET REPRESENTENT CHACUN L'HYDROGENE OU UN ACYLE, OU ENCORE FORMENT ENSEMBLE UN RADICAL CARBONYLE OU UN RADICAL(CF DESSIN DANS BOPI)DANS LEQUEL X REPRESENTE L'HYDROGENE OU UN RADICAL ALKYLE OU ALCOXY ET Y REPRESENTE L'HYDROGENE OU UN RADICAL ALKYLE, ALCOXY OU ARYLE.CES COMPOSES SONT DES SUBSTANCES DE CROISSANCE. ON LES UTILISERA EN PARTICULIER POUR AGIR SUR LE DEVELOPPEMENT VEGETATIF OU GENERATIF DE LEGUMINEUSES TELLES QUE LE SOJA. Novel brassinosteroid derivatives of the general formula I (in which R17 represents C8-C10-alkyl or -alkenyl, Z represents -CO-O- CH2- or -O-CO-CH2-, and R2 and R3 each represents H or acyl or together represent X representing H, optionally chlorinated C1-C4-alkyl or C1-C3- alkoxy and Y representing H, optionally chlorinated C1-C4-alkyl, C1-C3-alkoxy or optionally substituted aryl) and their manufacture. The novel compounds have a plant growth-regulating action, being particularly suitable for influencing the vegetative and generative growth of leguminous plants, for example soya bean plants, and accordingly may be made up with suitable carriers and/or auxiliaries into plant growth- regulating preparations and may be used for treating seeds, living plants and areas of land.