A new synthetic route to -silyl ketones involving two steps from readily available components is described. Recentlywe have described the generation of 2lithio derivatives (2) from 1,3-dithianes (1) and the application of these nucleophilic reagents to the synthesis of a wide variety of organic compounds, including aldehydes, ketones, l,n-diketones, a-hydroxy ketones, -keto acids, and -amino ketones.1 The

Until recently, broth cultivation techniques for Campylobacter pylori were unavailable. We developed a method to cultivate bacterial cells within 24 h in liquid media. Cultivation in broth depended on the adequate dispersion of appropriate gases. A static broth at 37°C in a GasPak jar (BBL Microbiology Systems, Cockeysville, Md.) with a CampyPak (BBL) envelope did not support growth after 5 days of incubation. A broth placed in a flask on a Gyrotory water bath shaker (150 rpm; New Brunswick Scientific Co., Inc., Edison, N.J.) fitted with a gassing hood connected to a gas mixture of 10% C02, 5% 02, and 85% N2 supported good growth. An initial inoculum of 105, 103 to 104, or 102 CFU/ml resulted in >108 CFU/ml after incubation for 24, 48, or 72 h, respectively. Under these conditions, the bacteria grew as motile, spiral bacilli rather than the oval and coccal bacilli occasionally reported. Several bases supported good growth when supplemented with serum. For the determination of basal growth conditions, brucella broth base was used. Fetal calf serum (1%) provided maximum growth. Vitox was not necessary for growth and did not augment growth. C. pylori grew over a wide optimal pH range of 5.5 to 8.5.

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Aseries of cephalosporins derived from cephalothin containing an ester-linked quinolonyl substituent at the C-10 position (C-10 quinolonyl-cephem esters) has been prepared and evaluated for in vitro antibacterial activity. The C-10 quinolonyl-cephem esters exhibited a broadened spectrum of activity when compared with cephalothin and the corresponding quinolones, including activity against /Mactamase-producing bacteria. cephalothin which culminated in the highly potent, broad spectrum agent le (Fig. 1). These compounds (la~le, Fig. 2, herein referred to as C-10 quinolonyl-cephem esters) possess a quinolonyl moiety attached at the C-10 position of cephalothin by an ester linkage through the quinolone-3-carboxylate. The synthetic procedures described in this report allow for the preparation of such C-10 quinolonyl-cephem esters with minimal formation of undesired z!2-cephem side products.Chemistry The preparation of la~le proceeded as shown in Fig. 3. The coupling of the 10-iodocephem 4-nitrobenzyl ester 211>12) with nalidixic acid sodium salt (3a) in A^N-dimethylformamide (DMF) gave a mixture of the desired z!3-cephem adduct (4a) and 30~40%of the thermodynamically more stable z!2-isomer. The quinolone carboxylate is sufficiently basic to abstract a proton from the cephalosporin Fig. 1. Structure ofle.

A lipase which hydrolyzes triglycerides (tricaprylin and trilaurin) and naphthyl laurate was obtained from the broth of Corynebacterium acnes cultures by ammonium sulfate fractionation. Ca2+ and sodium taurocholate stimulated activity of the enzyme. Ethylenediaminetetraacetic acid (EDTA) did not inhibit activity of the Ca2+-activated enzyme, but lipolytic activity was inhibited by EDTA in the absence of Ca2+. Tetracycline (10-4M) produced a slight inhibition of the lipase activity with 5 X 10-5 M or less showing no effect on the lipase activity. However, complete inhibition by tetracycline at 104 M was observed for Ca2+-activated enzyme. Tetracycline inhibition of the C. acnes lipase could be demonstrated at concentrations as low as 10-6 M.

Results of minimal inhibitory concentration tests with a diversity of bacterial strains showed that 9-chloro-9-(4-diethylaminophenyl)-10-phenylacridan (C-390) inhibited the growth of all microorganisms tested (other than Pseudomonas aeruginosa) at 25 jug/ml or less, whereas MICs obtained for P. aeruginosa ranged from 50 to >100 ,ug/ml. Therefore, C-390 was evaluated as a potential selective agent for P. aeruginosa in pseudomonas agar F. Recovery tests were conducted on this medium with 53 strains of P. aeruginosa, and the results were compared to those obtained in similar tests on commercially available selective media, i.e., pseudomonas isolation agar and Pseudosel agar. The results of these comparisons indicated that pseudomonas agar F with C-390 was significantly less inhibitory than Pseudosel agar and pseudomonas isolation agar and more selective than pseudomonas isolation agar. The incorporation of C-390 in pseudomonas agar F also provided a medium that was both selective and differential. Preliminary evidence also suggested that C-390 may be added to other basal media with comparable results.

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Legionella micdadei has been implicated as a cause of nosocomial pneumonia. There are no reports of L. micdadei pneumonia diagnosed by acid-fast stain of expectorated sputum. We report a case of L. micdadei pneumonia in which expectorated sputum harbored acid-fast bacteria that reacted specifically with fluorescent antiserum to L. micdadei, confirmed by culture. In a patient at risk for nosocomial infection, the differential diagnosis of a positive sputum stain for acid-fast bacilli should include L. micdadei in addition to mycobacteria. Therapy for L. micdadei infedction should be considered pending confirmation of the diagnosis.