In the search of new biologically active compounds and in continuation of our investigation on the synthesis of nitrogen-containing drimane and homodrimane sesquiterpenoids 1-3, we herein describe the preparation of iso-drimenoic acid amides (7a-c) from norambreinolide (1), according to the scheme given below. Reagents and conditions: a) P2O5, DMSO, CH2Cl2, 20°C, 40 min, Et3N, 20°C, 40 min, 93%; b) NaClO2, NaH2PO4, t-Bu-OH, 2-Me-2-butene, H2O, 20°C, 2 h, 94%; c) (COCl)2, C6H6, 20°C, 1 h, △, 1 h, 95%; d) R-NH2 (6a-c), CH2Cl2, 20°C, 24 h, △, 10 h. Starting drimenoic acid (4) for the preparation of amides (7a-c) was synthesized from norambreinolide (1) in the six-steps synthesis with an overall yield 55%. The reaction of acid (4) with (COCl)2 produced acid chloride (5), reactions of which with 2-amino-pyrimidine (6a), 4-amino-pyrimidine (6b) and 2- amino-pyrazine (6c) formed amides (7a-c). The structures of amides (7a-c) were established on the basis of their IR, 1H – NMR, 13C – NMR, 15N – NMR, and mass – spectral data. It is very likely that acid chloride (5) is formed as a result of the migration of a double bond △7(8) in acid (4) to △8(9) in acid chloride (5) in the reaction conditions. The newly synthesized amides (7a-c) are of a scientific and practical importance as compounds with a potential biological activity. 1. K. Kuchkova, A. Aricu, E. Secara, A. Barba, P. Vlad, N. Ungur, C. Tuchilus, S. Shova, Gh. Zbancioc, I.I. Mangalagiu, Med. Chem. Res., 2014, 23, 1559-1568. 2. K.I. Kuchkova, A.N. Aricu, E.S. Secara, A.N. Barba, P.F. Vlad, F.Z. Makaev, E. Melnic, V.Kh. Kravtsov, Chem. Nat. Compd., 2015, 51, 684-688. 3. A.N. Aricu, K.I. Kuchkova, A.N. Barba, I.P. Dragalin, S. Shova, N. Vornicu, E.K. Gorinchoi, E.S. Sekara, L.V. Lungu, M. Niculaua, N.D. Ungur, P.F. Vlad, Chem. Nat. Compd., 2016, 52, 1029-1036. 4. K.I. Kuchkova, Y.M. Chumakov, Y.A. Simonov, G. Bocelli, A.A. Panasenko, P.F. Vlad, Synthesis, 1997, №9, 1045-1048. 5. K.I. Kuchkova, A.N. Aricu, I.P. Dragalin, P.F. Vlad, Khim. Prir. Soedin., 2005, №2, 152-155.
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