Propionic Acid Ester Research Articles

High Moisture Corn Preserved with Esters of Propionic Acid for Lactating Cows

Forty lactating Holstein cows over 2 yr of age were used to compare rolled dry shelled corn with high moisture (75.6% DM) ground shelled corn preserved with esters of propionic acid (1% of corn weight) in a concrete bunker silo. Cows were fed complete mixed rations containing (dry basis) 34.9% corn silage, 20.0% alfalfa haylage, 33.6% corn grain, and 11.5% of soybean oil meal, vitamins, and mineral premix. Milk yields, its composition, feed intakes, and body weight changes were similar for cows fed dry corn and high moisture corn. Rumen proprionate was higher and isobutyrate and isovalerate were lower for cows fed high moisture corn than for dry corn diets. Rumen pH and ammonia were lower for cows fed high moisture corn than for those fed dry corn.

Enantiomer separation with capillary gas chromatography columns coated with cyclodextrins. Part I: Separation of enantiomeric 2‐substituted propionic acid esters and some lower alcohols with permethylated β‐cyclodextrin

AbstractThe applicability of permethylated β‐cyclodextrin as an enantioselective stationary phase for capillary gas chromatography has been investigated. Attention has been paid to its phase transitions in a temperature range of 40–200°C. The enantiomer separation of 2‐substituted propionates and some lower alcohols illustrates the pronounced selectivity of the permethylated β‐cyclodextrin relative to molecular geometry.

Electronic spectroscopy of tryptophan analogs in supersonic jets: 3-Indole acetic acid, 3-indole propionic acid, tryptamine, and N-acetyl tryptophan ethyl ester

The electronic spectroscopy of four different tryptophan analogs, 3-indole acetic acid, 3-indole propionic acid, tryptamine, and N-acetyltryptophan ethyl ester (NATE) has been studied in a supersonic molecular beam using laser-induced fluorescence and resonantly enhanced two-photon ionization. The electronic transition to the lowest excited singlet state occurs at 35 039, 34 965, 34 918, and 34 881±2 cm−1 for 3-indole acetic acid, 3-propionic acid, tryptamine, and NATE, respectively. The relatively small differences in the electronic origin transition frequencies suggests that the lowest excited singlet state for all of these moelcules is the 1Lb state. The spectra reveal that each of these molecules have stable conformers in the gas phase, analogous to our previously reported studies of tryptophan. A low frequency vibrational mode has been observed in 3-indole propionic acid, tryptamine, NATE, and tryptophan which involves motion of the side chain against the indole ring. We have observed that forming a van der Waals complex between tryptamine and a single methanol molecule causes the spectral features due to different conformers of the free molecule to collapse to a single line, suggesting that one particular conformer becomes the most stable species. This emphasizes the importance of including solvent interactions in any attempt to model the behavior of these molecules in solution.

Acetone, methyl ethyl ketone, ethyl acetate, acetonitrile and other polar aprotic solvents are strong inducers of aneuploidy in Saccharomyces cerevisiae

A diploid yeast strain D61.M was used to study induction of mitotic chromosomal malsegregation, mitotic recombination and point mutation. Several ketones (including acetone and methyl ethyl ketone) and some organic acid esters (including the methyl, ethyl and 2-methoxyethyl esters of acetic acid) and acetonitrile strongly induced aneuploidy but not recombination or point mutation. Only diethyl ketone induced low levels of recombination and point mutation in addition to aneuploidy. Related compounds were weak inducers of aneuploidy: methyl n-propyl ketone, the methyl esters of propionic and butyric acid, acetic acid esters of n- and iso-propanol and ethyl propionate. No mutagenicity was found with n-butyl and isoamyl acetate, ethyl formate, acetyl acetone (2,5-dipentanone) and dioxane. Methyl isopropyl ketone induced only some recombination and point mutation but no aneuploidy. Efficient induction was only observed with a treatment protocol in which growing cells were exposed to the chemicals during a growth period of 4 h at 28°C followed by incubation in ice for more than 90 min, usually overnight for 16–17 h. Aneuploid cells could be detected in such cultures during a subsequent incubation at growth temperature if the chemical was still present. Detailed analysis showed that there was a high incidence of multiple events of chromosomal malsegregation. It is proposed that the mutagenic agents act directly on tubulin during growth so that labile microtubules are formed which dissociate in the cold. When cells are brought back to temperatures above the level critical for reassembly of tubulin and allowed to grow, faulty microtubules are formed.

Acetic acid esters and permeable weak acids induce active proton extrusion and extension growth of coleoptile segments by lowering the cytoplasmic pH

In Avena coleoptile segments a decrease of cytoplasmic pH activates energy-dependent H(+) extrusion into the apoplast, thereby triggering extension growth. This sequence of events cannot be inhibited by cycloheximide and is induced by the following conditions and compounds. (i) A short anaerobic treatment of coleoptile segments results in the formation of lactic acid and an intracellular decrease of pH. For a period of 20 min after transfer to normal air, the growth rate is up to six times higher than the rate before anaerobiosis. (ii) Similarly, incubation of segments with CN(-) (0.1 mM) in the presence of oxygen causes and accumulation of lactic acid and a fall in cell-sap pH. After removing CN(-) a growth burst occurs. (iii) Higher concentrations of permeable acids (≧10 mM in buffer pH 5.8) induce extension growth. This growth is O2-dependent and therefore differs from the acid growth, which can be triggered under anaerobic conditions by acid buffers of pH≦5 via the direct increase of cell-wall plasticity. (iv) A short application of CO2-saturated buffer (pH 5.8) causes CO2-induced elongation growth; after a 3-min pulse the growth rate is enhanced for about 15 min. (v) Lipophilic esters of acetic acid or propionic acid, such as naphthylacetate, naphthylpropionate, phenylacetate, benzylacetate induce elongation growth. These compounds, when taken up into the cell, are hydrolized by esterases; the acids released lower the cytoplasmic pH (shown by the pH indicator, fluorescein). The highest esterase activity was found in a microsomal membrane fraction of coleoptiles. While the carboxyester-induced extension growth is completely inhibited under anoxia, the initial acidification of the bathing solution can still be observed. This decrease in external pH is obviously the result of ester hydrolysis, caused by damaged cells, and is not the result of pH changes within the cell-wall compartment. It is suggested that a fast uptake of carboxyesters and the shift in equilibrium caused by their internal hydrolysis leads to a continuous formation of acids which lowers the cytoplasmic pH and activates the ATP-dependent H(+) extrusion. In most experiments fusicoccin (a diacetic acid ester) acts similarly to naphthylacetate and the other carboxyesters, although quantitative differences exist. Therefore, it is possible that fusicoccin is effective partly on the basis of its ester characteristic. The effects observed are discussed with regard to the very narrow pH optimum of plasma-membrane H(+)-ATPases exhibiting their highest levels of activity at pH 6.5 (Hager and Biber 1984, Z. Naturforsch. C 39, 927-937).

Cellulose-Based Liquid Crystalline Polymers; Esters of (Hydroxypropyl) Cellulose

Abstract Propionic, n-butyric, isobutyric and phthalic acid esters of (hydroxypropyl)cellulose were prepared and characterized. The aliphatic esters were readily formed by reacting (hydroxypropyl)cellulose with the corresponding acid chloride at room temperature. The phthalic acid ester was formed by reacting phthalic anhydride with (hydroxypropyl)cellulose in pyridine at 45°C. The bulk aliphatic esters exhibit cholesteric reflection in the visible range of the spectrum. The wavelength of the reflection peak maximum, Λo, was measured spec-trophotometrically at different temperatures. Plots of Λo reached zero (i.e. the cholesteric pitch became infinite) at temperatures close to the anisotropic-isotropic phase transition temperatures. The latter temperatures were determined experimentally by polarizing micros-copy and differential scanning calorimetry, and were in the range 165°C ± 10°C for all cellulose derivatives studied in this work. The optical rotatory dispersion (ORD) and circular dichroism (CD) of t...

Some characteristics of Mn2(CO)10 as an initiator of radical addition and telomerization

1. The partial chain transfer constants in the telomerization of ethylene with CCl4, initiated by Mn2(CO)10, are 2.5–3 times greater than the corresponding constants in the analogous reaction, initiated by peroxides. 2. A substantial increase in the first constant C1, with a retention of the values of the higher constants, was observed when the same reaction was initiated by the Mn2(CO)10 + DMF system. 3. The initiating effect of Mn2(CO)10 in the reaction of methyl chloroacetate with ethylene and 1-hexene is manifested in cleavage of the C-Cl bond of the telogen. 4. The Mn2(CO)10 + CHCl3 system initiates -the radical addition of the methyl esters of isobutyric and propionic acid to olefins.

New functional allylic lithium reagents: gem-dialkoxyallyllithium reagents: a useful route to β-silyl- and β-stannylpropionate esters

The reaction of sec-butyllithium with acrolein dialkyl acetals in THF or in THF/Et 2O/pentane at -95°C results in formation of gem-dialkoxyallyllithium reagents, Li[CH 2CHC(OR) 2]. These react with organosilicon and organotin chlorides to give ketene acetals, R 3SiCH 2CHC(OR) 2 and R 3SnCH 2CHC(OR) 2. The acid hydrolysis of these products produces β-substituted propionic acid esters, R 3SiCH 2CH 2CO 2R and R 3SnCH 2CH 2CO 2R. Reactions of these lithium reagents with allyl bromide gave esters of 5-hexonoic acid, CH 2CH(CH 2) 3CO 2R (R = Me, Et).

Heats of vaporization of alkyl esters of formic, acetic and propionic acids

Heats of vaporization of ethyl, propyl, butyl esters of formic acid, methyl, ethyl, propyl and butyl esters of acetic acid and methyl, ethyl and propyl esters of propionic acid were measured. These measurements reassume and complete data known from the literature. From the combination of values of heats of vaporization, the cohesive and vaporization internal energies of the set investigated were computed in the dependence on temperature.

Esterolytic activity of blood serum in infants with hypertrophic pyloric stenosis.

Esterolytic activity of blood serum was determined in infants with hypertrophic pyloric stenosis and in healthy control children. The substrates hydrolyzed mainly by arylesterase (EC. 3.1.1.2), i.e. p-nitrophenyl esters of acetic, propionic and butyric acid were used. It was found that in infants with hypertrophic pyloric stenosis the rate of p-nitrophenyl propionate hydrolysis was significantly higher than that of the acetate or butyrate. In control group children all three substrates were hydrolysed at similar rates, and these were significantly lower than in infants with hypertrophic pyloric stenosis.

Studies of heterocyclic compounds. XVIII. Synthesis of 1-(substitutedphenyl)-2,3-tetramethylenepyrrolo[2,1-b]benzothiazoles.

1-(Substituted-phenyl)-2, 3-tetramethylenepyrrolo [2, 1-b] benzothiazoles (IV-2-IV-17) were synthesized from the correspoding 3-(substituted-phenyl) thiazolo [2, 3-b] benzothiazolium perchlorates (III) by the reaction of 1-morpholino-1-cyclohexene, an enamine. On reaction with cuprous cyanide p-substituted bromobenzene (IV-2) furnished benzonitrile (IV-23), which was converted into the corresponding 1-phenyl derivatives (IV) with various aliphatic functional groups at the para position of the phenyl moiety. On reaction with methylmagnesium iodide and subsequent acid hydrolysis IV-23 was converted into acetophenone (IV-24), which reacted with methyltriphenylphosphylene to give 2-phenylpropylene (IV-38). Hydroboration of IV-38 afforded 2-phenylpropanol (IV-39), which was oxidized into the corresponding propionic acid (IV-43), the sulfur atom being oxidized at the same time into sulfoxide. Deoxygenation of the ester (IV-44) was successfully carried out with PBr3 to obtain the desired α-phenyl substituted propionic acid ester (IV-45).

Carboxylesterases of human brain extract Purification and properties of a butyrylesterase

1. 1. A carboxylesterase (carboxylic-ester hydrolase, EC 3.1.1.1) from human brain extract was prepared to purity using DEAE-cellulose, Sephadex G-200, and fractionation with (NH 4) 2SO 4. The yield was about 20%. 2. 2. Esters of butyric acid were split faster than esters of acetic, propionic and valeric acid, and the enzyme is tentatively designated as a butyrylesterase. Thiocholine esters were split at low rates. 3. 3. The molecular weight was estimated as 340 000 using gel chromatography on Sephadex G-200. In isoelectric focussing the enzyme was resolved into several peaks ( pI 4.0–4.7). The low isoelectric point does not seem to be due to terminal sialic acid residues. 4. 4. The enzyme was irreversibly inhibited by diethyl-p- nitrophenyl phosphate ( k i = 206 mol −1 · 1 · s −1 ) and by diisopropylfluorophosphate. The carboxylesterase inhibitor bis-p- nitrophenyl phosphate and eserine did not inhibit the enzyme. 5. 5. The enzyme was progressively inhibited by p- hydroxy-mercuribenzoate , and reactivated by dithiothreitol and 2-mercaptoethanol. N- Ethylmaleimide inactivated the enzyme very slowly, whereas iodoacetate and iodoacetamide were without effect. 6. 6. Ca 2+, Mg 2+, and Zn 2+ or EDTA did not influence the enzyme activity.

Gas chromatographic determination of propoxyphene and norpropoxyphene in plasma

Propoxyphene and its major metabolite norpropoxyphene have been determined simultaneously by using gas chromatography. In order to avoid the on-column decomposition of the propoxyphene, derivatives were formed with the aid of lithium aluminium hydride, which cleaves the propionic acid ester of propoxyphene and reduces the norpropoxyphene amide. Promethazine was used as an internal standard. Propoxyphene and norpropoxyphene levels in plasma were determined in samples from six male volunteers receiving a single oral dose of 150 mg of propoxyphene hydrochloride in a sustained-release form (Abalgin Retard ®).

Fluorinations with potassium tetrafluorocobaltate(III) Part III. Fluorination of esters and acyl fluorides and some reactions of the derived polyfluoroacids

Esters of propionic, acrylic, succinic, maleic and acetylene dicarboxylic acid have been fluorinated over KCoF 4 to give mixtures containing polyfluoroacid fluorides which have been isolated as esters, separated and characterised. Propionyl and isobutyryl fluorides also gave polyfluoroacid fluorides and thence esters on fluorination, but with increasing difficulty as the chain is branched so that pivaloyl fluoride was not fluorinated. Propionyl chloride gave, in addition to the expected acid fluorides, some polyfluorochloro compounds. Some reactions of the new acids and esters are described including the synthesis of benzimidazoles.

The photochemical conversion of some heterocyclic acraldehydes into derivatives of propionic acid

Some 3-(triazolopyridyl)- and 3-(v-triazolyl)acraldehydes have been found to add methanol in high yield to give the corresponding propionates when irradiated through quartz or Pyrex. A keten intermediate is suggested, and a reaction scheme has been tested by deuteriation studies. Other hydroxylic solvents (water or t-butyl alcohol) can also be added to the acraldehydes, giving the corresponding propionic acid or t-butyl ester.

Telomerization of ethylene with methyl propionate and acetoacetic ester

1. The telomerization of ethylene with propionic acid, methyl propionate, and acetoacetic ester has been studied. 2. The rearrangement of the intermediate radicals of type (I, R=CH3CO) goes to a greater extent than for (I, R=CH3).

Ultrastructural demonstration of acetylcholinesterase activity of motor endplates via osmiophilic diazothioethers.

The ultrastructural chemical localization of acetylcholinesterase of motor endplates of rat intercostal muscle has been studied with three new esterase substrates. These substrates, although not specific for acetylcholinesterase, have differential affinities for various types of esterases; two of them (NTA and TAB) are hydrolyzed preferentially by acetyl esterase enzymes, and the third (TPB) is a propionic acid ester and is hydrolyzed preferentially by pseudocholinesterase and other esterases. The end-product of the enzymatic reaction is converted to a diazothioether (droplet form) and upon osmication this is converted to a coordination polymer of osmium which has ideal properties for electron microscopy.

Toxicity Test of Food Additives by the Disturbance of Life Cycles of Chlorella and Saccharomyces cerevisiae var. Sake (II)

According to the previous method, twelve sorts of official food preservatives and antimicrobials, chloramine B and T, n-butyl and n-propyl benzoate, p-oxybenzoate, propionic acid, butylsalicylate, and other carboxylic esters were examined. Results of the test were as follows:1. By the disturbance of life cycles of Chlorella and Saccharomyces, the bacteriostatic or bactericidal action was inspected easily as a comparative reference to bacteria.2. This method might be available as a comparative safety test of food preservatives or antimicrobials when used by the multiple dilution culture.3. In the case of acidic preservatives such as benzoic acid, salicylic acid or sorbic acid, the correlation of pH between additives and medium or food had great influence to the preservative action.4. Esters of acidic preservatives indicated generally a greater bacteriostatic action than that of the free acids.In this paper, the effect of preservatives or antimicrobials was tested only by addition of sugar as one of five principal nutrients.

PERMANGANATE–PERIODATE OXIDATION: VI. THE OXIDATION OF VARIOUS ALIPHATIC COMPOUNDS

A study was made of the reaction of the permanganate–periodate reagent with a wide variety of aliphatic alcohols, polyols, aldehydes, acids, oxy-acids, ketones, ethers, and esters. Saturated monols, ketones, and ethers, as well as acetic, pelargonic, pyruvic, lactic, and oxalic acids reacted only very slowly. Glycols, olefinic alcohols, and unsaturated acids were cleaved to give predictable end products. Activated alcohols and ethyl acetoacetate reacted at relatively high rates. Formic, glyoxylic, lactic, and malonic acids as well as 1,3-propanediol and 2,5-hexane dione reacted extensively and diethyl tartrate consumed as much oxidant as did tartaric acid. The oxidation of tetrahydrofurfuryl alcohol gave succinic acid instead of the expected tetrahydro-2-furoic acid. Saturated mono- and di-carboxylic acids, 3-hydroxy propionic acid, γ-valero lactone, and saturated esters were stable towards the reagent.

Influence of gonadal and adrenal cortical hormones on estrogen-induced depletion of pituitary gonadotropin content.

The FSH content of male rat pituitaries was reduced by doses of estradiol ranging from 0.004 to 0.4 mg/kg/day. Concurrent injections of testosterone or its propionic acid ester prevented the estradiol-induced depletion of FSH to an extent proportional to the size of the dose of the androgen and to the degree of androgenic effects on the sex accessory organs. Pregnant mare serum gonadotropins (PMS) at 50 RU/kg/day also prevented the depletion of FSH brought about by estradiol. Progesterone produced a significant reversal of the estradiol effect on pituitary FSH content, but this gonadal steroid was considerably less effective than testosterone. The effective dose of progesterone, 20 mg/kg, brought about slight ventral prostate growth in the estrogenized males. Desoxycorticosterone acetate and cortisone acetate were inactive at daily dose levels up to 20 mg/kg. Additionally, testosterone propionate, restored in part the FSH content of pituitaries of rats given daily injections of estradiol started 2 weeks b...