ANALYSIS OF 1,4-DIOXANE 287 Table III Recovery and Comparison of Direct Injection Gas Chromatographic and Birkel-FDA Procedures for Analysis of 1,4-Dioxane Dioxane Found, mg/kg Dioxane Added, mg/kg Birkel-FDA Direct GC 1.25 1.2 2 2.50 2.5 3 5.00 4.8 5 determined by analyzing spiked samples seven times each, was found to be 25% of the 1,4-dioxane level. Fifty-five alcohol ethoxylates, all manufactured using a base-catalyzed procedure and analyzed by this dual-column direct injection gas chromatographic method, did not contain a detectable level of 1,4-dioxane. These results have also been compared to those obtained using the FDA-sanctioned Birkel Method (6). As Table III shows, for alcohol ethoxylates spiked with dioxane and analyzed by both procedures, there is good agreement and recovery at the very low mg/kg level. CONCLUSION The above procedure has been used to screen a wide range of primary alcohol ethoxylates manufactured by Shell Chemical Company (NEODOL(D Alcohol Ethoxyl- ates. CTFA Adopted Name (9) PARETH). The ethoxylates tested were based on alcohols ranging from a C9/C•0/C n blend to a C•4/C•5 blend, and had ethylene oxide contents ranging from an average of 2.25 to 13 moles/mole of alcohol. The ethoxylates were manufactured using a base-catalyzed procedure believed to be broadly practiced in the industry. No 1,4-dioxane could be detected in these products using either the above procedure or the Birkel FDA method. Both methods have a detection limit of 0.5 mg/kg 1,4-dioxane. REFERENCES (1) M. F. Argus, J. c. Arcos and C. Hoch-Ligeti, "Studies on the carcinogenic activity of protein- denaturing agents: Heptocarcinogenicity of dioxane,"J. Nat. Cancer Inst., 35,949-958 (Dec., 1965). (2) C. Hoch-Ligeti, M. F. Argus andJ. C. Arcos, "Introduction of carcinomas in the nasal cavity of rats by dioxane," Br.J. Cancer, 24, 164-167 (1970). (3) R.J. Kociba, S. B. McCollister, C. Park, T. R. Torkelson and P.J. Gehring, "l,4-dioxane. I. 2-Year ingestion study in rats," Toxicol. Appl. Pharmacol., 30(2), 275-286 (1974). (4) M. F. Argus, R. S. Sohal, G. M. Bryant, C. Hoch-Ligeti and J. C. Arcos, "Dose response and ultrastructural alterations in dioxane carcinogenesis. Influence of methylchloanthrene on acute toxicity," Eur. J. Cancer, 9(4), 237-243 (1973). (5) National Cancer Institute, "Carcinogenesis Technical Report Series No. 80," (1978). (6) T. J. Birkel, C. R. Warner and T. Fazio, "Gas Chromatographic Determination of 1,4-Dioxane in Polysorbate 60 and Polysorbate 80,"Journ. of the AOAC, 62(4), 931-936 (1979). (7) Personal Communication. (8) Annual Book of ASTM Standards, Part 25, ASTM D-3606-77. (9) CTFA Cosmetic Ingredient Dictionary, 2nd Edition, Cosmetic, Toiletry and Fragrance Association, Washington D.C., 1977.

j. Soc. Cosmet. Chem., 31,289-297 (November 1980) Antimicrobial activity of N-glucosylrhodanines and N-glucosylthioureas SEUNG HO AN and WILLIAM O. FOYE, Department of Chemistry, Massachusetts College of Pharmacy and Allied Health Sciences, Boston, MA 02115. Received January 3, 1980. Presented at the 1979 Annual Scientific Meeting of the Society of Cosmetic Chemists, New York. Synopsis Rhodanine and rhodanine derivatives have shown significant inhibitory activity against bacteria, fungi, and some parasites, and have potential as preservative agents. No glycosylated derivatives of rhodanine or its derivatives have previously been evaluated as antimicrobial agents the presence of a sugar moiety should provide compounds of low toxicity. A series of N-(2,3,4,6-tetra-O-acetyl-/•-D-glucopyranosyl)- 5-aralkylidenerhodanines has been prepared and their antimicrobial activities against several organisms determined. Attempts to remove the acetyl groups by ammonia in methanol provided a synthetic method for obtaining N-glycosylthiourea. Use of other amines was found to give the substituted N-glyco- sylthioureas. Antimicrobial activities of these compounds against several microorganisms were found in several cases to be equal to or slightly better than those from rhodanine or glycosylated rhodanine derivatives. INTRODUCTION Many preservatives are available for use in cosmetics, but the actual options which face the cosmetic chemist and microbiologist, when they are dealing with a specific formula, may be very narrow. The difficulty in choosing a proper compound for a preservative is also the case for the synthesis of those compounds which should meet primary criteria such as water solubility and chemical and physical stability as well as biological activity. It was considered that N-glucosylthioureas and N-glucosylrho- danines might prove suitable as preservatives, and accordingly this study was undertaken. A large number of thioureas have been synthesized and found to be biologically active as antiviral (1,2) and antibacterial-antifungal (3,4) agents. Also, many rhodanine derivatives have been reported with significant inhibitory activities against virus (5,6), bacteria (7,8), fungi (9-11), and parasites (12,13). However, these compounds have not been used in cosmetics as preservatives because of their toxicities (14-16), and because of changes in color, viscosity, and pH in aqueous solution. In attempts to achieve 289