Di-p-bromobenzoate

The structure of brunsvigine (583) has been established by the X-ray analysis of the corresponding 0,0 -di-p-bromobenzoate (7a). Furthermore, the H-NMR spectra of brunsvigine together with several of its derivatives have been completely assigned, and the ORD and CD spectra of these compounds have been measured. The structure of 583 was related to other 5,1 lb-methanomorphanthri-dine alkaloids by methylation and other chemical transformations including a series of Hoffmann degradations (7b). 

TTie structure and absolute stereochemistry of brunsvigine (1 R = H) isolated from Brusvigia cooperii have been established on the basis of the X-ray crystallographic analysis of its OO -di-p-bromobenzoate. Recent n.m.r., c.d., and mass spectral studies are consistent with this assignment. Furthermore, chemical correlation of OO N-trimethylbrunsvigine picrate with 0-methyl-/3-isocrinamine metho-picrate, prepared from the known j8-isocrinamine (1 R = Me), was achieved. Hippeastrine (2) has been isolated from Clivia miniata and Hippeastrum vittatum. ... 

The stereochemistry of a chiral, intact carotenoid has not yet been solved by X-ray crystallographic analysis 174). Recently the crystal structure of capsanthin (2) di-p-bromobenzoate was reported 167) in support of the previous configurational assignment (see below). 

Pederin di - p - bromobenzoate metbanol solvate (absolute configuration)... 

Yamauchi H, Fijiwara T, Tomita T (1969) The crystal and molecular structure of 3p,12P-0-di-p-bromobenzo-ylpyxinol. Tetrahedron Lett 4245-4248... 

C27H38O, Isophorone condensation trienone, 43B, 256 C28H20f Di-p-anthracene, 31B, 112 46B, 192 C28H26Br04, Norbornadiene dimer di-p-bromobenzoate, 38B, 242 C28H28 f 9,10-Benzotricyclo[3.3.2.0 ]deca-3(7),9(10)-diene dimer, 43B, 256... 

Furusaki, A., Watanabe, T Matsumoto, T, and Yanagiya, M. (1968) The crystal and molecular structure of pederin di-p-bromobenzoate. Tetrahedron Lett., 9, 6301-6304. 

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