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A u s dem Organisch-chemischen Institut der Universitat Mainz Eingegangen a m 12. Dezemher 1955 ZU S.4MMENFA S S U N G : Durch Umsetzung von ,,alkoholischen" Bernsteinsaure-1,6-Hexandiol-Polyestern mit Bernsteinsaureanhydrid in Renzol werden kettenanaloge Polyester mit endstandigen Carboxylgruppen hergestellt . Die Titration dieser Carboxylgruppen ergibt Molgewichte bis -7 . lo3. Mit Phenylisocyanat in indifferenten Losungsmitteln reagieren Polyesterdicarbonsauren unter Kettenverlangerung und Bildung von kettenstsndigen Carbonslureanhydridgruppen. Die Umsetzung der Polyester-dicarbonsauren in Phenylisocyanat ohne Verdiinnungsmittel erfolgt kettenanalog unter Bildung von Carboxanilidendgruppen.Durch photometrische Anilinbestimmung nach der Hydrolyse konnen diese Endgruppen quantitativ bestimmt und Molgewichte berechnet werden, die mit den titrimetrisch erhaltenen Molgewichteri iibereinstimmen. Es werden weiterhin viskosimetrische Messungen a n Losungen der Polyester auspefiihrt. S U M M A R Y :By reaction of ,,alcoholic" poly-1,6-hexanediol-succinate with succinic anhydride in benzene solution chain-analogous polyesters with terminal carboxylgroups are obtained.Molecular weights of polyesters up to -7 . lo3 are determined by titration of the carboxyl end groups. Polyester-dicarboxylic acids react with phenylisocyanate in inert solvents by prolongation of chains, forming carboxyl anhydride groups. The reaction of polyesterdicarboxylic acids with phenylisocyanatc without diluent is a chain-analogous one. Terminal carboxylic acid anilide groups are formed. After hydrolysis these end groups are determined quantitatively by photometric rnea%urements of aniline formed. The molecular weights are calculated and agree with those obtained by titration. Viscosimetric measurements have been made.Die Darstellung lincarer Polyester mit alkoholischen Endgruppen und deren Umsetzung mit Phenylisocyanat zu kettenanalogen Polycsterdiurethanen wurde in der vorstehenden Mitteilung beschrieben.Wir versuchten nun auch, lineare Polyester rnit Carbosylendgruppen herzustellen und die Reaktionen dieser Endgruppen zit studieren. ') Teil der Dissertation Mainz 1952. D 77. *) Teil der zukiinftigen Dissertation Mainz 1955, D 77. 219

The guideline no. 206 for testing of chemicals of the Organization for Economic Cooperation and Development (OECD) comprising an avian reproduction test using the Japanese quail (Coturnix coturnix japonica; Termminck and Schlegel 1849) as pair-hold test organisms has been applied in a version that reduced the treatment period to 6 weeks without any pretreatment. In the present study bis(tri-n-butyltin)oxide, C.A. No. 56-35-9 (tributyltin oxide, TBTO) was examined by five participants in an interlaboratory comparison test. A comparable regimen of dosing was performed by all participants starting either with 24 or 60 mg/kg TBTO in the feed and ending with 150 or 375 mg/kg. Within this dose range no signs of toxicity in adults were observed. Substance-related effects however were obvious with regard to egg production, fertility, hatching success, and survival of 14 day-old chicks. A clear dose dependency was given regarding effects on egg weight and on hatchability. The no-observed-effect concentrations for these two parameters was 60 mg/kg TBTO, characterizing these parameters as the most sensitive in this investigation. With the presented set of test parameters further aspects of subchronic toxicity in adults and chicks can be assessed as well as the validity of the performed test. Comparing the results for most test parameters consistency is obvious, thus confirming the applicability of the presented test guideline.

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