OH 0.45 0.77 c NH, -0.48 -0.83 3-[5-(4-Acetamidophenyl)-2-tetrazolyl]propionic Acid (14). A solution of 5 g (0.022 mole) of 3-[5-(4-aminophenyl)-2-tetrazolyl]propionic acid 34 in 200 ml of Ac,0 was allowed to stand for 24 hr at room temperature. The reaction was diluted with 2 1. of water and the solid collected and dried. Recrystallization from MeOH gave 2.4 g (40%) of fine white needles, mp 218°.3-[5-(4-Phenylazophenyl)-2-tetrazolyl]propionic Acid (16). A solution of 10 g (0.043 mole) of 3-[5-(4-aminophenyl)-2-tetrazolyl> propionic acid (34) and 4.6 g (0.043 mole) of nitrosobenzene in 150 ml of warm glacial acetic acid was allowed to stand for 24 hr. The precipitate was collected, washed with MeOH, and recrystallized from THF-MeOH to give 9 g (65%) of red crystals, mp 234°.

Cephalosporin C (I), the amine (11), and derived cephalosporanic acids (111; R1 = H) are converted into new derivatives by replacing the acetoxygroup with various sulphur, nitrogen, and carbon nucleophiles.7-Aminocephalosporanic acid ( 11) is produced by the action of thiourea on 7-chloroacetamidocephalosporanic acid or spontaneously from 4'-chlorobutanamido-or 5'-chloropentanamidocephalosporanic acids as a result of intramolecular displacement.CONVERSION of the antibiotic cephalosporin C (I) into 7-aminocephalosporanic acid (11) and subsequent acylation to give a series of 7-acylaminocephalosporanic acids (111 ; R1 = H) have been de~cribed.l-~ We have converted such acids into their methyl esters (111; R1 = Me), lactones (IV), and I-oxides (VIII; Y = OAC).~ The stereochemistry of the oxides has not been studied. Hale, Newton, and Abraham described 5 the transformation of cephalosporin C (I) into the pyridinium betaine (VI; X = C,H5N+) and showed that a range of substituted pyridines formed similar derivatives (C, compounds) by replacing the acetoxy-group. The formation of a Bunte salt ( I X ; Y = S,O,Na R = [CH,],*CH(NH,)*CO,H), when cephalosporin C is treated with sodium thiosulphate was proposed 6 to account for the resulting increase in antibacterial activity. We have studied the substitution of the acetoxy-group in salts of 7-acylaminocephalosporanic acids (I11 ; R1 = H) by azide, NN-dimethyldithiocarbamate, thiobenzoate, and

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A new triterpene has been obtained by saponification of the oily lightpetroleum extract of tallow wood (Eucalyptus microcorys, fam. Myrtaceae), which, bearing a general similarity to the cycloartenol sub-group, has been named cycloeucalenol.cycZoEucaleno1 is a monohydric secondary alcohol, apparently C, lH,,O. It contains one ethylenic bond, present in a side chain terminated by the grouping -CH,*C(:CH,)*CHMe,. The occurrence of a cyclopropane ring was revealed by the action of hydrogen chloride and by the infrared absorption at 3050 cm.-l. Oxidation of the unsaturated acid-isomerisation products from demethylcycloeucalanyl acetate, a dihydro-derivative having the modified terminal group -CH,*CH,*CHMe,, gave a dilretone containing the transoid system -CO*C=CCO-but not identical with 7 : ll-dioxolanost-8enyl acetate.

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