Synthesis and Practical Applications of Brassinosteroid Analogs

Novel Brassinosteroid-Modified Polyethylene Glycol Micelles for Controlled Release of Agrochemicals

“…Brassinosteroids are steroid plant hormones that affect the vegetal physiological processes at very low concentrations (in the order of 10 –9 mol/L). , In this sense, brassinosteroids together with other phytohormones are expressed in the vegetal proteome and regulate growth, xylem differentiation, senescence, and disease resistance of the plants. − 24-epibrassinolide, 28-homobrassinolide, and different synthetic analogues of brassinosteroids are able to stimulate the germination of seeds and the growth and efficiency of crops and to promote photosynthesis and senescence. − Furthermore, different brassinosteroids and synthetic analogues of brassinosteroids are proposed as plaguicides as a result of their antiecdysteroid activity . Some brassinosteroids have been employed as potential agrochemicals because very small quantities (from 5 to 100 mg/ha) increase the yield and quality of several crops. , This regulatory effect is observed at concentrations 100 times smaller than those required for other vegetal hormones, and the interaction of the brassinosteroids with auxins and gibberellins in plants is well-documented …”

“…DI31 and S7 are two Cuban synthetic analogues of brassinosteroids widely employed as agrochemicals in different plantations, with increases in crop yields of 5–30%. ,, Particularly, DI31 has been commercialized for agriculture as a liquid extract at 100–1000 ppm in 50 vol % ethanol/water and other additives to ensure stable dispersions (Biobras-16) for almost 20 years . However, the described potential benefits are not completely expressed in plants because these compounds are quickly metabolized, and two or three foliar spray applications are often needed, increasing the economic cost of their use. , Another problem with current commercial formulations of DI31 is the preparation, storage, and transport as hydro-alcoholic suspensions, which also increases costs associated with the agrochemical application. It is envisaged that, if the duration of their action may be prolonged, their use as agrochemicals would be made more feasible.…”

“…6 However, the described potential benefits are not completely expressed in plants because these compounds are quickly metabolized, and two or three foliar spray applications are often needed, increasing the economic cost of their use. 6,10 Another problem with current commercial formulations of DI31 is the preparation, storage, and transport as hydro-alcoholic suspensions, which also increases costs associated with the agrochemical application. It is envisaged that, if the duration of their action may be prolonged, their use as agrochemicals would be made more feasible.…”