✍ Scribed by Cavill, G. W. K. ;Vincent, J. M.
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The preparation of the methyl, ethyl, n‐propyl, iso‐propyl, n‐butyl, sec.‐butyl, iso‐butyl, n‐amyl, iso‐amyl, n‐hexyl, (2‐methyl)‐amyl, n‐heptyl and (2‐ethyl)‐hexyl esters of 4‐hydroxybenzoic acid is described.
Results are reported for the toxic action of these esters tested against three moulds: Aspergillus niger, Byssochlamys fulva and Penicillium roqueforti. The inhibitory action is described principally in terms of b (slope of the log. dosage/log. response curve) and an inhibitory index (I), being the reciprocal of the millimolar concentration required to attain a suitable level of inhibition.
Where its determination has been possible (A. niger and B. fulva), b can be regarded as substantially the same for all the esters tested. The logarithm of I plotted against chain length showed a general increase from methyl to hexyl with much less, or no, increase from hexyl to heptyl. The three organisms showed, however, specific differences in their detailed reaction to successive esters. Branched esters, tested against A. niger, were close too, and usually slightly less than, the values for the corresponding normal esters. Differences are reported for the reaction of A. niger to the free acid. Experience with other compounds, particularly as constitution affects b is briefly noted.
Some physico‐chemical aspects of inhibition by the above compounds are discussed.
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## Abstract The preparation is described of the methyl 4‐__n__‐amoxy‐, methyl 4‐__n__‐butoxy‐, ethyl 4‐__n__‐propoxy‐, __n__‐propyl 4‐cthoxy‐ and __n__‐butyl 4‐methoxy‐benzoates, and their hydrolysis products‐the 4‐__n__‐alkoxybenzoic acids.
constituents like fucosterol and the algal terpenes which are at present being investigated. Russel-Wells has shown that the fats increase with depth of emergence from 0.16% in L. digifata to 3.6% in Pelvefia canaliculata. Work in progress indicates that fucoidin also increases with depth of emergen
determining sulphur given in the B.P. gave low results and tecourse was made to a wet oxidation using bromine in nitric acid. This accords with the U.S. National Formulary and it is suggested that such a method should be introduced into the B.P. owing to the presence of volatile oils in ichthammol.
A total of ten C18 fatty esters containing an azido group and another chemical function (ethylenic, bromo, epoxy, hydroxy, methoxy, acetoxy or vinyl) were synthesised from methyl ricinoleate. Methyl di-and triazidooctadecanoate were also derived from methyl oleate and ricinolcate, respectively. The
A. ,tiger, growing in the presence of p-aminobenzoic acid and its lower alkyl esters, departs significantly from linearity in media of approximate pH 3 to 5, containing nitrate nitrogen. This effect is not observed where media are of p , ~ 6 to 7 or nitrogen is supplied solely as the ammonium ion or