Reductive cleavage by sodium in liquid ammonia of the lignin of cotton-plant stems

Summary 1. The reductive degradation by metallic sodium and liquid ammonia of the lignin of green cotton-plant stems has confirmed the presence in them of three types of structural units: syringyl, guaiacyl, and p-hydroxycoumaryl.2. The preliminary sonication of the plant with ultrasound leads to a decrease in the amount of products containing methoxy groups in the aromatic nucleus, particularly syringyl structures.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 643–646, September–October, 1976.