Twenty-one substituted 1,4-naphthoquinones and five 8-quinolinols and copper(II) chelates were tested for antifungal activity against Candida albicans and Trichophyton mentagrophytes. Compounds containing electron-releasing or weak electron-withdrawing groups in the 2 and 3 positions of the 1,4-naphthoquinone ring were the most active against C. albicans at pH 7.0 in the presence of beef serum in the following order: 2-CH3O = 2,3-(CH3O)2 greater than 2-CH3 greater than 2-CH3S greater than 2-NH2 greater than 2,6-(CH3)2. For T. mentagrophytes under the same conditions the inhibitory 1,4-naphthoquinones contained the substituents 2-CH3O greater than 2,3-(CH3O)2 greater than 2-CH2S greater than 2-CH3 greater than 2-CH3(NaHSO3) greater than 2-NH2 greater than 2-C2H5S, 3-CH3 greater than 2,6-(CH3)2 greater than 2,3-CL2 greater than 5,8-(OH)2.

Excitation and fluorescence spectra, excited singlet state, protolytic equilibrium constants for the equilibria between the cations and zwitterions, fluorescence quantum yields, and fluorescence limits of detection for 8-hydroxyquinoline and 29 of its derivatives are given. The derivatives studied include fluoro, chloro, bromo, iodo, sulfo, and thiocyano substituents in either the 5-or the 7-positions on the ring or in both positions and methylation of the phenolic oxygen at the 8-position on the ring. Excited singlet state pK,* values range from -6.2 for the 5-iodo-7-sulfo-8-hydroxyquinoline to -9.6 for the 5,7-disulfo-8-hydroxyquinoline. Analytical detection limits for the 8-hydroxyquinoline and its derivatives in concentrated sulfuric or perchloric acid were between 10-6 to 10-EM. Fluorescence quantum yields varied as expected from a high value (0.31) for 8-hydroxyquino-

Two germination inhibitors from bean rust uredospores were identified as the cis and trans isomers of methyl 3,4-dimethoxycinnamate. They appear to be the "self-inhibitors" previously described from these spores.

Thirteen 2-alkynoic acids and their methyl esters (C3--C12, C14, C16, and C18) were tested against Aspergillus niger, Trichoderma viride, and Myrothecium verrucaria in Sabouraud dextrose agar at pH 4.0 and 5.6. Toxicity to Candida albicans, Trichophyton mentagrophytes, and Mucro mucedo was determined in the same medium at pH 5.6 and 7.0 in the absence and presence of 10% beef serum. The fungitoxicity of the acids was influenced by chain length, pH of the medium, and absence or presence of adsorbents. The toxicity of the esters was influenced primarily by chain length and to a lesser extent by the pH of the medium and the presence of beef serum. The order of activity of the 2-alkynoic acids is C10=C11=C12 greater than C14=C16 greater than C9 greater than C8 greater than C7. When compared with other fatty acid analogs, the order of fungitoxicity on a weight basis is 2-alkynoic acids greater than 2-alkenoic acids greater than alkanoic acids greater than 2-bromoalkanoic acids greater than 2-fluoroalkanoic acids. There is an inverse relationship between chain length and pKa of the acids, suggesting that partition behavior is a fundamental determinant of fungitoxicity along with the effect of adsorbents.