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31.
F. Khuong-Huu D. Herlem-Gaulier MM. Qui Khuong-Huu E. Stanislas R. Goutarel 《Tetrahedron》1966,22(10):3321-3327
The following alkaloides have been extracted from the leaves of Buxus balearica Willd.: cyclomicrophylline-B, cycloprotobuxines A, C and D, baleabuxine (N-isobutyryl-baleabuxine-F), buxamine-E and buxaminol-E (already reported), N-isobutyryl- and N-benzoyl-baleabuxidine-F, baleabuxoxazine-C, N-isobutyryl- and N-benzoyl-baleabuxidienine-F, N-isobutyryl-baleabuxaline-F, the structures of which are proposed. The stereochemistry of baleabuxidines and baleabuxoxazines is established on the base of chemical correlations between these two groups and cyclomicrophyllines. 相似文献
32.
Single crystals of potassium hydrogen squarate monohydrate have been prepared, and the unit cell, space group and crystal optics determined:a = 8·641(1),b = 10·909(1),c = 6·563(2)Å, = 99·807(5) °,Z = 4,P21/c,n
= 1·411(1),n
= 1·674(1),n
= 1·793(2), 2V(–) = 59·1(8) °,n
¦¦t,n
:a = 2·3(2) ° in obtuse . Infrared and oriented Raman spectra have been obtained, and compared with the spectra of both the acid and the [C4O4]2– ion. The squarate ring is itself very nearly orthorhombic, with symmetry axes parallel to the C-C bonds. The rings lie approximately in (001), with the C-C bonds aligned witha andb. 相似文献