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Isoindole derivatives R 0140 Sulfur Ylides. Part 13. Synthesis and Intramolecular Cyclization of Keto-Stabilized Sulfur Ylides. -Novel keto-stabilized sulfonium mono-and bisylides (VII), (XVII) and (XIII) are synthesized and their behavior under conditions of intramolecular cyclization is studied. Only α-ylide (XVII) undergoes an intramolecular cyclization furnishing pyrrolizidinedione derivative (XVIII). -(GALIN, F. Z.; SAKHAUTDINOV, I. M.; LAKEEV, S. N.; EGOROV, V. A.; FATYKHOV, A. A.; MAIDANOVA*, I. O.; Russ.

Regiospecific synthesis of conjugates containing a diterpenoid fragment and a pyrazole-ring pharmacophore by 1,3-dipolar cycloaddition of diazomethane to allenoates in the presence of Et 3 N was demonstrated.Pyrazoles are very important heteroaromatic compounds due to their broad distribution in natural products and pharmacologically active compounds [1-3]. Many pyrazole-containing compounds such as Celebrex [4], rimonabant [5], and Viagra [6] were successfully commercialized as drugs. Methyl maleopimarate (MEMPA) was obtained by the known method from levopimaric acid and maleic anhydride [7,8] and is a convenient and available reagent for synthesizing compounds with anti-inflammatory, antiulcer, fungicidal, and other activities [9][10][11][12]. In continuation of research on potential biologically active compounds, we synthesized conjugates with a diterpene fragment and pyrazole-ring pharmacophore. The key reaction was 1,3-dipolar cycloaddition of diazomethane to allenoates.Allenes 4a-c were synthesized from N-substituted amino acids 2a-c, which were obtained via condensation of MEMPA (1) with glycine, E-alanine, and J-aminobutyric acid in refluxing DMF. The reaction of N-substituted amino-acid chlorides 2a-c with Et 3 N passed through ketenes 3a-c, which reacted with methyl(triphenylphosphoranylidene)acetate to give allenoates 4a-c in yields of 63, 67, and 70%, respectively [13] (Scheme 1). The structures of the synthesized allenes were proved by physicochemical analytical methods. Thus, 13 C NMR spectra were characterized by resonances for two terminal allene C atoms C-2c and C-4c at G 96.13 and 91.17 ppm for 4a; 90.16 and 89.7 ppm, 4b; 91.86 and 88.56, 4c; and also central C atom C-2c at G 210.37 ppm for 4a; 212.89, 4b; and 212.44, 4c.

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A keto stabilized sulfur ylide, containing phthalazinedione fragment, was synthesized. During thermolysis, the ylide forms the product of intramolecular cyclization of pyrrolo phthalazinedione structure.

New sulfur bis ylide was obtained from 3 amino 3 phenylpropionic acid and pyromellitic dianhydride. Its intramolecular cyclization proceeds regioselectively, leading to 3,4,11,12 tetrahydro 2Н,6H indolizino[2,1 f]pyrido[2,1 а]isoindole derivative in 66% yield. Phospho rus bis ylide of similar structure gives a cyclization product in 10% yield.

Производные дитерпеновых кислот, в частности малеопимаровая кислота, являются легко доступными соединениями на основе растительного сырья, находят применение для синтеза биологически активных веществ и для получения материалов, пригодных в промышленности. Целью данной работы является синтез жирорастворимых дитерпенсодержащих конъюгатов фуллерена С 60 на основе бром-и хлорметилкетонов N-замещенных малеопимаримидов. Синтез конъюгатов фуллерена С 60 с циклопропановым кольцом осуществлен по реакции Бингеля. Показано, что хлорметилкетоны являются более выгодными циклопропанирующими агентами по сравнению с бромметилкетонами. Полученные метанофуллерены с дитерпеновым фрагментом обладают способностью растворяться в растительных маслах, где их содержание достигает масс. 6%.