Abstract

Novel water-soluble polymers containing diosgenin moieties have been synthesized in order to study the proper conditions for the design of phytoactive formulations carrying brassinosteroid analogs. Samples are obtained by radical copolymerization between acrylamide (AM) and diosgenin monomaleate (DMM) at different initial feed compositions. The resulting copolymers present variable steroidal molar fractions ranging from 0.01 to 0.12, as calculated by means of ¹H NMR spectroscopy. Mao–Huglin method is employed for the estimation of monomer reactivity ratios, which renders 16.884 and 0.0024 for AM and DMM, respectively. Surface tension measurements evidence that copolymers with steroidal content below 0.1 exhibit aqueous stability with micelle formation. Controlled release of diosgenin moieties is achieved through alkaline hydrolysis of the monomaleate ester and followed by conductometry. The process displays second order kinetics with a suitable rate constant value for agricultural applications (0.061 L mol⁻¹ s⁻¹). The proposed formulation can also be extended for other applications of steroidal compounds.

摘要

为了研究设计带有油菜素类固醇类似物的植物活性制剂的适当条件，已经合成了含有薯os皂苷元部分的新型水溶性聚合物。在不同的初始进料组成下，通过丙烯酰胺（AM）和薯os皂素单马来酸酯（DMM）之间的自由基共聚获得样品。所得共聚物的甾体甾体摩尔分数变化范围为0.01至0.12（以¹为单位计算）1 H NMR光谱。Mao-Huglin方法用于估计单体反应率，这使得AM和DMM分别为16.884和0.0024。表面张力测量表明，甾族含量低于0.1的共聚物具有胶束形成的水稳定性。薯gen皂苷元部分的控制释放是通过单马来酸酯的碱水解并随后进行电导测定来实现的。该方法显示具有适合农业应用的速率常数值的二阶动力学（0.061 L mol ^-1 s ^-1）。所提出的制剂还可以扩展为甾族化合物的其他应用。