Frequencies and intensities of normal vibrations of the representative biologically active steroidal phytohormones homobrassinolide and (22S,23S)-24-epibrassinolide were calculated in the framework of our original approach combining classical analysis of normal vibrations using molecular mechanics and quantum-chemical estimation of absolute intensities. IR absorption bands were interpreted by comparing experimental and theoretical spectra. The impacts of structural differences in the molecular side chains on IR spectra in the region 1500–950 cm^–1were evaluated.

中文翻译：

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高油菜素内酯与（22S，23S）-24-表油菜素内酯Ir光谱的计算和比较分析

具有代表性的生物活性甾体植物激素高油菜素内酯和（22S，23S）-24-表油菜素内酯的典型振动的频率和强度是在我们原始方法的框架内进行计算的，该方法结合了常规振动的经典分子分析和绝对强度的量子化学估计。通过比较实验光谱和理论光谱来解释红外吸收带。评估了分子侧链结构差异对1500–950 cm ^–1区域内IR光谱的影响。