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Eperuic acid, a new bicyclic diterpene carboxylic acid, CmH,,O,, is the chief constituent (ca. 85%) of an oleo-resin derived from the wallaba tree (Eperuafalcata and other Eperua spp.) of British Guiana. The acid and its principal compounds are liquid.Selenium dehydrogenation of the methyl ester, which can readily be prepared by the Fischer-Speier method, yields naphthalene derivatives, including 1 : 2 : 5-trimethylnaphthalene. The ozonolysis products of methyl eperuate are formaldehyde, formic acid, and a keto-ester CmH8,0,, and, when the latter is dehydrogenated, pimanthrene ( 1 : 7-dimethylphenanthrene) is obtained. These indications of a relation to the manoijl-agathic acid group of diterpenes were substantiated by stepwise oxidation of dihydroeperuic acid, through an acid CIOHS,OO and methyl ketone C18HIP0, to a C,, acid which yielded 1-ethyl-2 : 5-dimethylnaphthalene when aromatised and decarboxylated with selenium. Eperuic acid is therefore 5-(4-carboxy-3-methylbuty1)decahydro-1 : 1 : 10-trimethyl-6-methylenenaphthalene.isolated after the addition of dilute hydrochloric acid gave the hydroxy-estev (VIII ; R = Me, R' = OH) as a colourless oil (2.5 g., 70%), b. p. 160-162"/0~1 mm., nb8 1-500 (Found : C, 74.2; H, 11-2. C2&3,03 requires C, 74-0 ; H, 11.2%).Cyclisation of the Keto-ester (VII ; R = Me).-A solution of the keto-ester (10 g.) in toluene (100 c.c.) was gradually mixed with alcohol-free sodium methoxide (1-7 g.), and after 2 hr. a t room temperature, was heated under reflux for 2 hr. After cooling, the product was treated Oxidation of MetJzyl E$evuate.-(i) W i t h ozone. 10.3 ; N, 4.3%).

1,4‐Benzochinon‐N,N′‐dibenzolsulfonylirnin (I) und das Naphthochinon‐Analogon (IV) reagieren mit Diphenyldiazomethan (II) zu den Addukten (III) bzw. (V).

3-Hydroxyquinolieinium salts are readily brominated to give Pbromo-3-hydroxyquinolizinium salts (3).The conversion of the 4-bromo3-hydroxyquinolizinium salts to 3-hydroxy-Lquinolizone ( 5 ) and the preparation of two quinolizinium phenol betaines 9 and 10 are described. I n previouswe have reported the synthesis and properties of I-and of 2-hydroxyquinolizinium salts. As expected, the 1-hydroxyquinolieinium salts were phenolic and underwent electrophilic substitution in position 2, l t 2 while the 2-hydroxyquinolizinium salts behaved more as quinolizones, as has been reported also for the 4-hydroxy ~e r i e s .~ Electrophilic substitution occurs in all three hydroxyquinolieinium salts1-3p5 with an ease surprising in a system carrying an over-all positive charge. In the reactions of the Z-hydroxyquinoliziniuni salts, no electrophilic substitution was observed in the 3-position (behaviour reminiscent of naphthalenes or isoquinolines) and the 3-hydroxyquinolizinium salts represent an interesting case where the ''naphthalene" pattern of substitution requires the electrophile to attack the position of expected lower electron density (position 4). I n fact, as is shown below, the site of bromination is position 4 and the "naphthalene" pattern is preserved.The synthesis of 3-hydroxyquinolizinium bromide (2, X = Br) from the diethyl acetal (1, R = C2H5) has been briefly reported16 but no yield was recorded, We have obtained the 3-hydroxyquinolizinium bromide (2, X = Br) from the dioxolane (1, R = -CH2-) in 96% yield, giving 76% over-all yield from 2-(2-pyridyl)-l13-dioxolane, and have also prepared the picrate and nitrate.7 The 3-hydroxyquinoliziniuni bromide (2) reacted readily with bromine in hydrobromic acid to give an 80% yield of a bromohydroxyquinolizinium bromide subsequently shown to have structure 3 (X = Br). This bromohydroxyquinolizinium salt reacted with silver acetate in hot acetic acid to give 3,4-dihydroxyquinoliziniuni bromide (4) , presumably via the unstable 3-hydroxy-4-acetoxy derivative. Unlike the previously reported 1,Bdihydroxyquinolizinium salt2 the 3,4-dihydroxyquinolizinium bromide was hydrolyzed by water, losing a proton to give 3-hydroxy-4-quinolizone (5) insoluble in water, but soluble in (1) For part VI11 of this series, see A. Fozard and G. Jones. (7) Professor C. K. Bradsher has informed us that he has obtained 3-hydroxyquinoliainium bromide in 48% over-all yield by a similar route, but has made no attempt t o isolate the intermediate quaternary pyridinium salt. 3030 (1964). organic solvents. The quinolizone 5 showed strong absorption a t 3424 cm. -l (intramolecularly hydrogenbonded OH) and a t 1640 cm. (pyridone carbonyP), 4 5 6 7To establish finally the position of the pyridone carbonyl in the quinolizone 5 and hence the site of bromination, the quinolizone 5 was catalytically reduced using Adams catalyst in methanol. Reduction ceased after two molecules of hydrogen had been absorbed ; properties of the reduction product (strong infrared absorption at 1640, 1590 and 1540 cm.-' in the pyr...