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Pressure-area curves have been measured for monolayers of ten lecithins (16:0–20:0, 16:0–11-methyl-18:0, 16:0–15-methyl-18:0, 16:0–22:1, 16:0–22:6, 18:0–22:6, 20:0–18:2, 18:3–16:0, 18:2–18:2 and 18:3–18:3) and eight fatty acids (18:0, 18:1, 18:2, 18:3, 20:4, 22:5, 11-methyl-18:0 and 15-methyl-18:0). Subtraction of the areas of the consituent fatty acids from the areas of the lecithin molecules in monolayers gave an estimate of the area contributed by the polar group. The effective areas thus obtained were found to range 3-fold in value. This result suggested that the orientation of the polar group in monolayers can vary depending upon the structures of the fatty acid chains in lecithin molecules. Mixed monolayers of each lecithin and cholesterol were investigated in order to find the molecular features of lecithin molecules responsible for condensation in monolayers by cholesterol. Condensation by cholesterol occurred in those lecithins that form expanded films, most strongly with those molecules that have a segment of saturated hydrocarbon chain extending nine or more carbons from the car☐yl group. The condensation between cholesterol and lecithins in monolayers has been interpreted in terms of cohesion between the saturated straight chain hydrocarbon segment of lecithin and either the ring system of cholesterol or other similar saturated segments in lecithin molecules.

A wide variety of alcohols, applied topically or injected into pupae of the yellow mealworm, Tenebrio niolitor L., exhibit juvenile hormone activity. Inclulded among these comipounds are saturated and unsaturated alcohols with 8 to 15 carbon atoms, in straight-or branched-chains. Ether derivatives of several of these alcohols fuirther enhance the activity.

A LARGE number of compounds have been shown to mimic the action of insect juvenile hormone. These include terpenoids (and derivatives) of somewhat similar structure to the major cecropia oil hormone1–3, and a number of non-terpenoid compounds, apparently having less obvious structural relationship with the hormone, for example juvabione4, aromatic compounds5–7 and saturated straight chain ethers8.

In skin from two patients with hereditary ataxic polyneuritis, the composition of long, straight chain α-hydroxy fatty acids was normal, and the concentration of these acids was at the lower limit of the range in six control subjects. The content and composition of hydroxy fatty acids in myelin from the brains of young rats fed a high phytol diet was normal, although phytanic acid represented 2.8% of the myelin fatty acids. These results do not support previous suggestions that the symptoms in hereditary ataxic polyneuritis result from a deficiency in straight chain α-hydroxy fatty acids.

We report a one-pot formation of 2,4-diolefinic or 2,4,6-triolefinic monocarboxylic acids, R-(CHCH)2or3-COOH, by decarboxylative condensation of an optionally α,β-unsaturated aldehyde with glutaconic acid, HOOC-CH2-CHCH-COOH as straight chain C4-extender. The reaction is broadly applicable to saturated and unsaturated aldehydes and opens up a simple gateway to valuable organic products and reactive intermediates.

This work continues our study of the mesomorphic properties of the p-n-alkoxybenzylidenep-fluoroanilines. Previous studies have shown that the straight chain homologues, with the number of carbon atoms in the chain ranging from 4 to 8, form smectic phases. In this paper we describe H NMR studies of the homologues with n 4, 5 and 8 and the synthesis and properties of a chiral branched chain derivative, (S)-p-2-methylbutyloxybenzylidene-p-fluoroaniline. This compound is not mesomorphic, but does show solid state polymorphism. From an optical, electro-optical, DSC and X-ray diffraction study we infer that the higher temperature crystalline form is a CrE phase.

A method of comparing the sum of the total energies of fragment molecules has been applied to the interpretation of simple cleavage and rearrangement reactions in electron-impact mass spectrometry for the straight chain aliphatic acids.

Three coals were swollen in a series of straight-chain amines. The degree of swelling increased with increasing chain length of the amine. However, the molar quantity absorbed by each coal was nearly constant for all the amines. The results suggest that all the absorbed amine interacted with specific sites within the coal.

Four samples of sunflower seed were surface washed with boiling hexane to remove waxes and hydrocarbons. Measurement of waxes in oil extracted from washed and unwashed seed showed greater than 92% removal of waxes. In addition, straight chain hydrocarbon content of the oil was substantially reduced. The composition of the material removed is shown.

Treatment of [{Rh(η-C3H5)2Cl}2] with [Fe(CO)4-(PPh2H)] in benzene in the presence of CO affords the mixed metal tetranuclear derivative [{RhFe(µ-PPh2)2(µ-CO)(CO)3}2], the structure of which has been determined X-ray crystallographically.

A method for the catalytic condensation of acetylenes with the acid chlorides of unbranched aliphatic acids was found.

Convolvulus pluricaulis (Chois) (Family: Convolvulaceae) (Hindi: Shankhapushpi), widely grown in the northern part of India, was analyzed for its fatty acids and waxy constituents. Straight chain hydrocarbons (C22–C33), fatty acids (C14–C28), and fatty alcohols (C24–C32) were found in the whole plant 95% aqueous ethanol extract. Hydrocarbons (C27, C31, and C33), fatty acids (C14, C16, and C18:2), and alcohols (C26, iso-C28, iso-C30, and C32) were the major components.

Small amounts of the methyl geranates occur in the essential oil of hops although the major methyl C10 unsaturated esters are straight chain compounds.

IN 1951, we described a semimicro chromatographic method for the separation and determination of the C4–C10 volatile fatty acids1. In that publication a description was given of the preparation of a silica gel which proved to be highly suitable for this separation. In that method, which is based on the principle of Ramsey and Patterson2, the fatty acids up to C10 are separated on a column of silicic acid, using methanol as the immobile solvent, isooctane as the mobile solvent and bromcresol green as the indicator. Since this method is quick and simple and never fails to give excellent results, we have tried to work out an identical method for the determination of the higher saturated fatty acids C10–C20.

Macht called attention to the fact that it is not necessary to have complex chemical compound containing nitrogen in its molecule to produce local anesthesia. He showed that the simple aromatic compound, benzyl alcohol, exhibited marked local anesthetic properties when studied by different pharmacological methods.1 During a pharmacological study of 23 isomeric octyl alcohols, Macht and Schroeder discovered that these straight chain alcohols all produced marked local anesthesia and, furthermore, that combinations of these acted synergistically.2 These findings suggested an inquiry into the possible local anesthetic properties of other aliphatic alcohols. In connection with a study of 18 primary aliphatic alcohols of the fatty acid series made jointly in the Laboratory for Organic Chemistry, directed by Professor E. Emmet Reid, Johns Hopkins University, and in this pharmacological laboratory, tests were made to determine whether any of these alcohols exerted a local anesthetic action.As a starting point for...

Crude bile, when applied to keratinstripped human skin in a cream vehicle at acid pH, under occlusion, produced noticeable pruritus after a period of 15 to 17 hours. At neutral or alkaline pH, no pruritus resulted. Purified, unconjugated sodium deoxycholate and chenodeoxycholate in a cream vehicle at acid pH also produced pruritus. Purified cholate sodium and sodium lithocholate, as well as synthetic straight chain anionic and neutral detergents failed to induce pruritus under the same experimental conditions. In complete biliary obstruction, chenodeoxycholate seems to be mainly responsible for the pruritus.

Fifty-three patients having contact dermatitis on the fingertips showed positive patch tests with several vegetables the commonest being garlic, onion, tomato, and carrot in that order of frequency. Of several preparations, made from garlic onion, tomato, and carrot, the juices used as such gave the maximum number of positive patch test reactions. Lyophilization of the juices led to false-negative patch tests in some cases. Patch tests in the controls were positive in some cases but these were probably cases of latent hypersensitivity, because some of them, like the patients, showed positive reactions even with the diluted juices. The antigens in garlic and onion were extractable in water, ether, acetone, or alcohol and were also present in the essential oils of these vegetables. Infrared spectra of the essential oils of garlic and onion were similar and showed straight chain acids, esters, and methylene groups. Clinically, there was no suggestion of cross-sensitivity between onion and garlic.

Gas liquid chromatography used to separate and identify a mixture of C5 to C10 straight chain hydrocarbons.

The lipid-soluble extract of the brown alga Cystophora torulosa has yielded a complex mixture of polyketide-derived alkenyl resorcinols and a phloroglucinol, together with two straight chain polyenes. Two polyprenyl chromans were also isolated in low yield.

A problem in which students are to derive a general expression for the number of cis-trans isomers in a "symmetric" straight chain polyene when there are n double bonds.

Rate and activation data have been obtained for the protiodeacylation in 89.8%(w/w) sulphuric acid of 10 alkyl mesityl ketones, with straight chain or branched chain alkyl groups, and of four diacylmesitylenes. The reactions have been analysed in terms of a sequence of two or three component ψ-first-order processes.

Values of the enthalpy, entropy and free energy of solution and hydration are reported for cyclopentanol, cyclohexanol, cycloheptanol, butan-2-ol, pentan-3-ol, hexan-3-ol and heptan-4-ol. Aqueous solutions of cyclic alcohols are thermodynamically more stable, mainly because of entropy effects, than those of the corresponding open chain secondary alcohols. ΔH°h varies linearly with ΔS°h, but the values for cyclic and secondary aliphatic alcohols lie on different straight lines.Parameters in the equation ΔH°h=α+β(ΔS°h+ 45) were calculated for all classes of monofunctional compounds so far investigated. The dependence of α on the type of functional group and on the type of hydrocarbon chain, open or cyclic, in which the latter is inserted is discussed.

Precise conductance measurements on dilute aqueous solutions of cyclic and straight chain quaternary ammonium iodides at 298 K are reported. The results are analyzed with the Fuoss-Hsia and Pitts equations for Λ(c) and are shown to provide some evidence for a slight amount of ion association which varies systematically with cation size and is most marked for the larger cations. The ionic resistivity (1/λ°+) of the cation increases by a constant amount (2.1 × 10–3Ω cm–2 mol) per CH2 group and can be related to estimates of the cation volumes V+ by the equation λ°+V⅔+=q.

Alkyl xanthates have been prepared from a number of normal, iso, and secondary alcohols containing from two to seven carbon atoms. The relative promoter activity of these xanthates has been determined by flotation tests on typical copper and lead ores. The promoter activity attains a maximum at from four to five carbon atoms in the alcohol. The promoter activity of the branched chain alcohol xanthates is greater than that of the corresponding normal or straight chain alcohol xanthates.

The Knudsen effusion method has been used to measure vapour pressures from the solid and liquid phases of the ethyl esters of the straight-chain C16, C18, C19, C20, C22, and C23 monocarboxylic acids. Standard heat and entropy terms are evaluated and the former are discussed in relation to the phase structures.

The metabolism of straight-chain saturated hydrocarbons has been demonstrated in the goat, rat and chicken. Studies with [1-14C]octadecane and [1-14C]hexadecane shwoed that the hydrocarbons were converted directly to fatty acids of the same chain length. Since both the initial substrates were symmetrical molecules with a methyl group on either end, the reaction must be omega oxidation. The studies have suggested a widespread occurrence of the oxidation in various tissues, and among widely divergent animal types. Although, only tracer quantities of hydrocarbons were administered, many intriguing questions for further study have been indicated.

The effects of straight-chain carboxylic acids on cathode overpotential during electrodeposition of copper were studied by galvanostatic methods at current densities up to 0.020 A-cm -2. No modification of the chargetransfer mechanism of copper deposition occurred. Overpotential increments caused by lengthening of the carbon chain can be correlated with the reduced concentrations of the carboxylic acids in accordance with Traube's rule. This can be rationalized in terms of the general relation between adsorbability and solubility of the additive. The general behavior is consistent with the blocking theory of additive function according to which overpotential increments are directly dependent on additive adsorbability. The fractional surface coverage calculated from overpotential increments appears to fit a Langmuirtype isotherm from which the free energies of adsorption of the carboxylic acids can be determined. The magnitudes of these free energies are consistent with physical adsorption forces. A relation was derived between the free energy of adsorption and the free energy contributions from the carboxyl group and the carbon chain. This shows that the longer the chain, the higher the adsorbability.

Nitrophenylhydrazones, notably 2,4-dinitrophenyl-hydrazones (2,4-DNPH), are among the most widely used derivatives for mass spectral characterization of carbonyl compounds. Mono-2,4-DNPH's of n-aldehydes of C5 or more and n-ketones of C6 or more exhibit prominent fragmentation peaks: the aldehydes giving strong peaks at masses 224 and 206, methyl ketones at masses 238 and 178, and ethyl ketones at masses 252 and 178. All show a distinct peak at M-35. Mass 182 is reported to be significant for mono-2, 4-DNPH using the time-of-flight mass spectrometer. Spectra of two steroid mono-2, 4-DNPH's run in this laboratory showed M-35 as the only characteristic peak shared with the straight chain series and not the characteristic bis-2, 4-DNPH peaks.

A PREVIOUS communication1 has described the interlamellar sorption of straight chain amines by graphic acid. Attention was then directed to a break in the curve of spacing against chain-length, occurring between 9 and 10 C-atoms per molecule.