Derivatives of 1,4-cyclohexadienyl-substituted -amino acids have been made from ß-aminopenicillamo acid, 7-aminocephalosporanic acid, and 7-aminodesacetoxycephalosporanic acid. The compounds exhibit considerable activity against a variety of Gram-positive and Gram-negative organisms in vitro.

B. From the Aldehyde 6.-A solution of 0.51 g (1.0 mmol) of 6, 0.13 g (1.0 mmol) of sodium thiophenoxide,14 and 1.0 ml of N,N-dimethylformamide was stirred for 40 min. Water (25 ml) was added and the resulting mixture was extracted with 3 X 10 ml of methylene chloride. The methylene chloride solution was washed with 2 X 7 ml of water and dried. The solvent was evaporated and residual oil was chromatographed on a silicic acid (100 mesh) column with ethyl acetate. The effluent was separated into a homogeneous fraction which crystallized from a mixture of benzene and petroleum ether after a seed of the phenylthioazetidinone 9 was added, 87.6 mg (19.9%), tic Rt was iden-

Pyrolysis of geissovelline at 280°p roduced a white solid which had a uv spectrum corresponding to that of geissovelline and not a carbazole or a iV-acetylcarbazole. 9-Acetyl-1,2,3,4-tetrahydro-6,7-dimethoxycarbazole.-A mixture of 300 mg of 1,2,3,4-tetrahydro-6,7-dimethoxycarbazole, 0.5 g of anhydrous sodium acetate, and 3 ml of acetic anhydride was refluxed for 3 hr under nitrogen. The solvent was evaporated and the residue was distributed between chloroform and water. Evaporation of the chloroform gave 9-acetyl-l,2,3,4tetrahydro-6,7-dimethoxycarbazole, which was crystallized from ether and sublimed (0.1 mm): mp (136-137°(lit.19 mp 136°); uv max (95% EtOH) 260 nm (e 23,500), 285 (9380); proton nmr (CDCla) 1.80 (m, 4, C-2 and C-3 CH2), 2.48 (s, 3, NCOCH3), 2.52 (m, 2, C-l or C-4 CH2), 2.77 (m, 2, C-l or C-4 CH2), 3.89 (s, 6, aromatic OCH¡¡), 6.76 (s, 1, aromatic H on C-5), 7.91 (s, 1, aromatic H on C-8). 9-Acetyl-6,7-dimethoxycarbazole .-A mixture of 200 mg of 9acetyl-1,2,3,4-tetrahydro-6,7-dimethoxycarbazole and 300 mg of 30% palladium/charcoal in 5 ml of n-hexyl ether was refluxed and stirred for 3 hr under nitrogen. The mixture was filtered hot and the cooled filtrate was diluted with petroleum ether (bp 30-60°). The product crystallized slowly. Three recrystallizations from ethanol gave colorless needles of 9-acetyl-6,7-dimethoxycarbazole: mp 123-124°after drying at 80°( 0.1 mm); uv max

No abstract

54, developed with a mixture of 1-propanol and 1% ammonium hydroxide in proportions 7:3, it moved with an R¡ 0.66. With the same mixture, the R¡ of D-glucosamine was 0.50, D-galactosamine 0.46, synthetic and natural Dgulosamine 0.55 and 2-amino-l,6-anhydro-2-deoxy-(3-D-galactopyranose 0.57.17 The natural and the synthetic XIV migrated at the same speed, either developed with the same mixture of solvents, or with the mixture sec-butyl alcoholacetic acid-water in proportions 4:1:1.Methyl 2-Acetamido-3,4,6-tri-0-acetyl-2-deoxy-j3-D-gulopyranoside (XVII). (a) From Synthetic n-Gulosamine Hydrochloride (XV).18-A solution of 215 mg. of crude synthetic sirupy D-gulosamine hydrochloride5 (XV) was dissolved in 19 ml. of methanol. After addition of 0.5 g. of silver acetate and 1 ml. of acetic anhydride, the mixture was left overnight at room temperature. After heating to boiling, the silver salts were filtered off and the filtrate evaporated in vacuo.The residual sirup was dissolved in 20 ml. of a 2% solution of hydrogen chloride in absolute methanol and refluxed for 2 hours. After cooling, the solution was neutralized with lead carbonate, the filtrate then treated with hydrogen sulfide, filtered through a double layer of Darco G-60 and Celite, and evaporated in vacuo.The residual sirup was acetylated overnight with 2 ml. of absolute pyridine and 2 ml. of acetic anhydride. Both reagents were removed by codistillation with dry toluene, and the residue was dissolved in chloroform and chromatographed on silicic acid. Elution with mixtures of ether and ethyl acetate 1:1, and with pure ethyl acetate, gave 163 mg. of crystalline fractions. Recrystallization from a mixture of acetone and ether afforded 116 mg. (32%) of needles, with a double m.p. at 118-119°and 124-125°, [a]83d -54