preparation of glycol 16. Hydrolysis of the intermediate osmate ester furnished 577 mg of crude material, which gave 243 mg of homogeneous, but amorphous, glycol on chromatography over Florisil. The glycol thus produced was dissolved in 5 ml of dry benzene and was treated directly with a solution of 384 mg of lead tetraacetate in 7 ml of anhydrous benzene. After 15 min at room temperature, the reaction mixture was worked up as previously described, yielding 214 mg of crystalline residue: A : : :3.67, 5.80, and 5.94 1.1.Attempts to purify a small sample of the keto aldehyde 36 by chromatography (alumina) and subsequent crystallization from methylene chloride-petroleum ether gave an isomer, mp 21 5-216", A, " : 2.81, 3.65, and 5.83 p, for which structure 37 is suggested.Anal. Calcd for G4H2604: C, 76.17; H, 6.92. Found: C, 76.23; H, 7.05.In view of this difficulty the remainder of the crude keto aldehyde above was reduced directly with lithium aluminum hydride in ether as described for the reduction of keto ester 33. Chromatography of the reduction product (Florisil) and crystallization from ethyl acetate-petroleum ether yielded a sample of glycol 34, mp 210.5-211.5", that was indistinguishable from the specimen derived from keto ester 33.Abstract: Through a combination of chemical and spectroscopic techniques (notably nuclear magnetic resonance and mass spectrometry) it has been possible to show that vallesiachotamine, an alkaloid isolated from the Peruvian Apocynaceae Vallesia dichotoma Ruiz et Pav, possesses structure I. A likely biogenetic route to this unusual structure is discussed.xtensive studies"6 in our laboratory on the con-
Tarichatoxin (C(11)H(17)N(3)O(8)), a potent neurotoxin recently isolated in pure form from the eggs of the California newt, Taricha torosa, has been found to be identical to tetrodotoxin from the ovaries of Sphoeroides rubripes, the Japanese Fugu or puffer fish. As yet this substance has been detected only in a single family of fish, Tetraodontidae, and in a single family of amphibia, Salamandridae.
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