Synthesis of Nitrogen‐Containing Derivatives of (18α,19β)‐19‐Hydroxy‐2,3‐secooleanane‐2,3,28‐trioic Acid 28,19‐Lactone |
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Authors: | Andrey V Shernyukov Ilya Ya Mainagashev Dina V Korchagina Alexander M Genaev Nina I Komarova Nariman F Salakhutdinov Genrikh A Tolstikov |
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Institution: | N.?N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, RU‐630090 Novosibirsk, (fax: +7?383?3309752) |
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Abstract: | The object of this study is the interaction of the cyclic anhydride 2 of (18α,19β)‐19‐hydroxy‐2,3‐secooleanane‐2,3,28‐trioic acid 28,19‐lactone ( 1 ) with primary and secondary amines. It was shown that the products of steric control (the corresponding 2‐amino‐2‐oxo‐3‐oic acids=2‐amides) were formed solely upon the opening of the anhydride cycle by secondary amines (Scheme 2), whereas the interaction with primary amines yielded a mixture of isomeric amides (Scheme 10). In the latter case, the solvent provided a noticeable effect on the reaction selectivity, which was demonstrated in the case of 4‐methoxybenzylamine. The interaction between the resulting 3‐amides and oxalyl chloride yielded the corresponding cyclic imides, whereas under these conditions, 2‐amides formed spiropyrrolidinetriones (Scheme 4). |
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Keywords: | 2 3‐Secotriterpenoids Cyclic imides Pyrrolidinetriones Oxazolidinediones Spiro compounds Oxalyl chloride |
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