Month: December 2022

Walker, James B. published the artcileFurther studies on the mechanism of transamidinase action: transamidination in Streptomyces griseus, Recommanded Product: Formamidine disulfide dihydrochloride, the publication is Journal of Biological Chemistry (1958), 1-9, database is CAplus.

cf. C.A. 51, 8169d. In contrast to mammalian kidney transamidinase, that of S. griseus does not react with glycine. Like the kidney transamidinase, it catalyzes reversible arginine-ornithine and canavanine-ornithine transamidinations. The concept of an enzyme-amidine intermediate in transamidination reactions is supported by (a) the occurrence of the arginine-ornithine exchange reaction, coupled with specificity considerations, and (b) the fact that the formamidine moiety of the intermediate can be trapped with HONH₂ to form hydroxyguanidine. Formamidine disulfide is a potent inhibitor of transamidinase. It is suggested that its inhibitory action results from the formation of a mixed disulfide with an essential sulfhydryl group on the enzyme. A sensitive colorimetric assay for hydroxyguanidine is described.

Journal of Biological Chemistry published new progress about 14807-75-1. 14807-75-1 belongs to ethers-buliding-blocks, auxiliary class Salt,Thiourea,Amine,Aliphatic hydrocarbon chain, name is Formamidine disulfide dihydrochloride, and the molecular formula is C11H19N, Recommanded Product: Formamidine disulfide dihydrochloride.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Tashika, Yoshio published the artcileSynthesis and properties of 1,1′-dithiodiformamidine hydrohalide, Related Products of ethers-buliding-blocks, the publication is Yakugaku Zasshi (1961), 1519-22, database is CAplus and MEDLINE.

A solution of 23 g. (H₂N)₂CS, 200 mL. H₂O, 40 mL. 95% EtOH, and 460 mL. 2N HCl, while cooling, treated dropwise with 74 mL. 50% EtOH containing 3 mol H₂O₂ at 5°, 900 mL. Et₂O added, and the mixture kept overnight at 0° gave 30 g. 1,1′-dithiodiformamidine (I): 2HX (X = Cl), m. 181°; picrate m. 154°. Similarly were prepared I (oxidizing agent, reaction medium, X in I, m.p., and m.p. of picrate given): SO₂Cl₂, absolute EtOH, Cl, 180°, 154°; p-MeC₆H₄SO₂Cl, Me₂CO, Cl, 180°, 153°; H₂O₂, 3N HBr, Br, 195-6°, 154.5°; Br, absolute EtOH, Br, 195-6°, 165°; Br, CHCl₃, addition product, 182°, 164°; iodine, H₂O, iodine, 78°, 154°; iodine, C₆H₆, addition product, 89°, 154°; H₂O₂, 3N HI, iodine, 82°, 154°. I (X = Cl) was the most stable and I (X = iodine) the most labile, liberating iodine. I was soluble in H₂O but not in organic solvents. Addition of organic solvent to the solution of I (X = iodine) immediately started liberation of iodine.

Yakugaku Zasshi published new progress about 14807-75-1. 14807-75-1 belongs to ethers-buliding-blocks, auxiliary class Salt,Thiourea,Amine,Aliphatic hydrocarbon chain, name is Formamidine disulfide dihydrochloride, and the molecular formula is C39H35N5O8, Related Products of ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Shier, W. Thomas published the artcileInhibition of acyl coenzyme A:lysolecithin acyltransferases by local anesthetics, detergents and inhibitors of cyclic nucleotide phosphodiesterases, HPLC of Formula: 637-58-1, the publication is Biochemical and Biophysical Research Communications (1977), 75(1), 186-93, database is CAplus and MEDLINE.

Acyl coenzyme A:lysolecithin acyltransferase [9027-64-9] activity in microsomal preparations from rat liver, rat heart, and rabbit gastric mucosa was inhibited by a series of tertiary amine local anesthetics, detergents, and some inhibitors of cyclic nucleotide phosphodiesterases. Aspirin [50-78-2] and indomethacin [53-86-1] cause elevated lysolecithin/lecithin ratios in the stomachs of mice after oral administration. Inhibition of acyltransferase activity in microsomal preparations by local anesthetics correlated with reported anesthetic potencies at approx. 1/100 reported therapeutic dosages. In BHK-13 cells acyltransferase activity was inhibited at 1/3 to 1/10 the concentrations that have been reported to cause alterations in the mobility and topog. of cell surface receptors.

Biochemical and Biophysical Research Communications published new progress about 637-58-1. 637-58-1 belongs to ethers-buliding-blocks, auxiliary class Inhibitor, name is 4-(3-(4-Butoxyphenoxy)propyl)morpholine hydrochloride, and the molecular formula is C14H10O4S2, HPLC of Formula: 637-58-1.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Schuster, Ingeborg I. published the artcileA carbon-13 NMR study of the 1:1 hydrogen bond between trifluoroacetic acid and aromatic ethers in deuteriochloroform, HPLC of Formula: 2944-47-0, the publication is Journal of Organic Chemistry (1991), 56(2), 624-31, database is CAplus.

From the measured values of the equilibrium constants and ¹³C NMR shift changes for 1:1 hydrogen bonding of trifluoroacetic acid with 2-alkyl- and 2,6-dialkylanisoles and 7-alkyl-2,3-dihydrobenzofurans in deuteriochloroform, conclusions are drawn concerning the stereochemistries of the hydrogen bonded complexes. The data indicate that hydrogen bonding of the planar 2-alkylanisoles may involve rotation of the methoxy group about the aryl-OCH₃ bond, the rotational angles ranging from 13° (anisole) to 43° (tert-butylanisole). The values of log K₁ correlate roughly with the torsional potential for methoxy group rotation in anisole, recently obtained by means of quantum mechanics, and with the angle-dependent electron densities at the methoxy oxygens that have been calculated for these o-alkylanisoles. The equilibrium constants for hydrogen bonding of the 2,6-dialkylanisoles also follow the predicted order of increasing methoxy oxygen electronic charge. The results for the rotationally rigid 2,3-dihydrobenzofurans are compatible with preferential involvement of the oxygen sp² lone electron pair in hydrogen bond formation.

Journal of Organic Chemistry published new progress about 2944-47-0. 2944-47-0 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 2-Isopropylanisole, and the molecular formula is C15H14O, HPLC of Formula: 2944-47-0.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Schmidt, Andrea C. published the artcileThe Role of Molecular Structure in the Crystal Polymorphism of Local Anesthetic Drugs: Crystal Polymorphism of Local Anesthetic Drugs, Part X, Recommanded Product: 4-(3-(4-Butoxyphenoxy)propyl)morpholine hydrochloride, the publication is Pharmaceutical Research (2005), 22(12), 2121-2133, database is CAplus and MEDLINE.

This report is the resume of a comprehensive investigation on the solid-state properties and the crystal polymorphism of the structurally homogeneous class of local anesthetic drugs. The goal is to explore the relationship between crystal polymorphism and mol. structural features. A salt form (mostly the hydrochloride) as well as the free base of 24 local anesthetics has been characterized by means of thermomicroscopy, differential scanning calorimetry, pycnometry, Fourier transform IR, Fourier transform Raman, and solid-state NMR spectroscopies, as well as x-ray diffraction methods (single crystal, powder). Based on the thermochem. data, the relative thermodn. stabilities of the different crystal forms of each polymorphic system were evaluated and visualized as semiquant. energy/temperature diagrams. This study is the first step in recognizing relationships between the structure and the solid-state properties within this limited group of active substances with common structural elements. The results clearly show that there are certain relationships, but, to understand the phenomenol. behavior in more detail on a mol. level, more structural information must be collected and analyzed by computational methods.

Pharmaceutical Research published new progress about 637-58-1. 637-58-1 belongs to ethers-buliding-blocks, auxiliary class Inhibitor, name is 4-(3-(4-Butoxyphenoxy)propyl)morpholine hydrochloride, and the molecular formula is C17H28ClNO3, Recommanded Product: 4-(3-(4-Butoxyphenoxy)propyl)morpholine hydrochloride.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Sahasrabudhey, R. H. published the artcileThiocyanamides and sulfonitriles: their constitution and identity, SDS of cas: 14807-75-1, the publication is Journal of the Indian Chemical Society (1950), 524-6, database is CAplus.

Thiocyanamide-HCl (I) was made from “amidothiotriazole” (II) by the Freund and Schander procedure [Ber. 29, 2500(1896)]. Oliveri-Mandalà (C.A. 9, 71) showed the “amidothiotriazoles” were really thiocarbamic acid azides; he made the HCl salts of phenyl-, tolyl-, and ethylthiocarbamic acid azides and the salts of the corresponding thiocyanamides, which he called sulfonitriles. I has saline characteristics, shown by its solubility in H₂O and alc. and insolubility in ether, CHCl₃, CCl₄, and C₆H₆. Aqueous solutions were highly acid because of hydrolysis. The free base could not be isolated, but addition of alkali precipitates S, and thiourea and NH₂CN are formed in solution Thiocyanamide salts liberate iodine from aqueous KI solutions Reduction of I in H₂O with Zn and HCl evolved large quantities of H₂S, and when a portion treated with excess NaOH solution gave no precipitate of S, absence of unreduced thiocyanamide was indicated. The remainder was made ammoniacal, the Zn precipitated as ZnS with H₂S, and filtered; the filtrate on concentration deposited crystals of thiourea in a sirupy residue of NH₂CN. Thiocyanamide salts: nitrate, m. 82° or 140° (decomposition); picrate, m. 154° or 164° (decomposition); HBr salt, m. 185-90° (decomposition); HCl salt, m. 186° (decompose). The m.ps. were identical with, and did not depress, those of the corresponding salts of [H₂NC(:NH)S]₂ (II) (Proc. Indian Sci. Congress, 1948, Pt. III, p. 25). Formation of thiocyanamide from H₂NCSN₃ and the identity of its empirical composition with that of II (HCl salt, CSN₂H₄Cl (?)), the oxidation product of thiourea suggests that they may be identical. The constitution is still being investigated. The aromatic thiocyanamides or sulfonitriles can not be the same as the corresponding formamidine disulfides because the aryl derivatives of the latter are known not to exist, while the free bases from the salts of the former have been made and the mol. weights determined O.-M. (C.A. 17, 738) suggested pentacovalent N structures, which is untenable. Fischer and Besthorn [Ann. 212, 316(1882)] and Hugershoff [Ber. 36, 3134(1903)] say that they are the same as the corresponding 2-aminobenzothiazoles. Comparison of m.ps. given by O.-M. (C.A. 9, 71) with corresponding arylaminothiazoles almost proves identity. Aniline sulfonitrile, C₇H₆N₂S, m. 122-3°, 2-aminobenzothiazole, C₇H₆N₂S, m. 123°; ο-toluidine sulfonitrile, C₈H₈N₂S, m. 138-40°, 2-amino-4-methylbenzothiazole, C₈H₈N₂S, m. 140°.

Journal of the Indian Chemical Society published new progress about 14807-75-1. 14807-75-1 belongs to ethers-buliding-blocks, auxiliary class Salt,Thiourea,Amine,Aliphatic hydrocarbon chain, name is Formamidine disulfide dihydrochloride, and the molecular formula is C2H8Cl2N4S2, SDS of cas: 14807-75-1.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Rovira, Santiago published the artcileAlkaline hydrolysis with high-boiling alcohols, Category: ethers-buliding-blocks, the publication is Annales de Chimie (Paris, France) (1945), 660-700, database is CAplus.

Compounds which are hydrolyzed with difficulty by EtOK or AmOK are saponified by using KOH in PhCH₂OH (I), (CH₂OH)₂ (II), or HOCH(CH₂OH)₂ (III). With nitriles and amides, the liberated NH₃ is titrated at intervals and in this way the kinetics of the reaction is studied. Amides such as AcNH₂, EtCONH₂, PrCONH₂, MeOCH₂CONH₂, BzNH₂, phthalimide, and Bz₃N are quant. saponified when boiled for 1 h. with KOH in I. OC(NH₂)₂ (IV) under these conditions requires 3 h. With II in lieu of I, IV is saponified in 2 h., and with III, in 45 min. OC(NH₂)NHPh and OC(NH₂) NHC₆H₄OEt are saponified in 1-2 h. with KOH in III while OC(NHPh)₂ is not attacked. With Ph-substituted amides, PhNH₂ is formed. Nitriles such as p-MeC₆H₄CN, PhCH₂CN, Ph(CH₂)₃CN, C₁₂H₂₅CN, PhMeCHCN, PhMe₂CCN, PhCH₂CHPhCN, CH₂(OH)CH₂CN, C₅H₁₁OCH₂CN, and amygdalin, when boiled with KOH in I, are quant. saponified in 1 h. while PhCN requires 2 h. PhBuCHCN is 85% saponified in 4 h. and PhBu₂CCN only 11% in 4 h. due to steric hindrance. H₂NCO₂Et and H₂NCO₂CH₂CHMe₂ with KOH in III are quant. saponified in 90 min. Bu, cyclohexyl, and m-xylyl allophanates and KOH in I are not completely saponified but with KOH in III, allophanates are quant. hydrolyzed in 1.5 h. Semicarbazones of the low-mol. ketones and aldehydes are readily saponified in 1-2 h. with KOH in III while the saponification is retarded with the nature of the radical. While Me abietate is saponified with EtOK only 50% in 4 h., it is saponified quant. with KOH in I in 4 h. Saponification of glycerol abietate with 0.5 N EtOK requires 8 h., with 0.1 N PhCH₂OK only 1 h. Carnauba wax is saponified with 0.5 N EtOK in 4 h. and with 0.1 N PhCH₂OK in 1 h. Boiling of caffeine for 1 h. or theobromine with KOH in III for 8 h. liberates 1 mol. NH₃ and 2 mols. NH₂Me. From theophylline 27.4% N is split off as NH₃ and NH₂Me after 25 h. (calculated for 3 N, 23.33%, for 4 N, 31.11%); from uric acid, 26.73% N after 27 h. (calculated for 3 N, 25.0%, for 4 N, 33.33%); and from xanthine, 35.42% N after 71 h. (calculated for 3 N, 27.63%, for 4 N, 36.24%). These results show that the velocity of decomposition depends upon the substituent at the N atoms. Finally, attempts are made to replace halogens in aromatic rings by OH with the preparation of phenols. While the halogen in PhBr, p-C₆H₄Br₂, o-BrC₆H₄Me, 2,3,5-Br₃C₆H₂OH, 2,5,6-bromo-m-xylenol, 2-C₁₀H₇Br, and eosin is almost quant. split off with KOH and I at 250°, the Cl in PhCl and in p-C₆H₄Cl₂ is split off only 10-15% at 250-300°

Annales de Chimie (Paris, France) published new progress about 16332-06-2. 16332-06-2 belongs to ethers-buliding-blocks, auxiliary class Amine,Aliphatic hydrocarbon chain,Amide,Ether, name is 2-Methoxyacetamide, and the molecular formula is C3H7NO2, Category: ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Poole, Colin F. published the artcileSelection of calibration compounds for selectivity evaluation of wall-coated, open-tubular columns for gas chromatography by the solvation parameter model, Application of 2-Methoxynaphthalene, the publication is Journal of Chromatography A (2020), 461500, database is CAplus and MEDLINE.

To facilitate faster selectivity evaluation of wall-coated, open-tubular columns using the solvation parameter model a reduced set of calibration compounds is identified and validated for the temperature ranges 60-140°C and 160-260°C. The Kennard-Stone uniform mapping algorithm is used to identify the calibration compounds from a larger database of compounds with known retention properties previously adopted for column selectivity evaluation. Thirty-five compounds for each temperature range are required to minimize the standard deviation of the system constants used for selectivity evaluation and to minimize differences between system constants determined by conventional calibration and the reduced calibration compounds The models for the reduced calibration compounds on ten siloxane-based and poly(ethylene glycol) stationary phases have a coefficient of determination of 0.984 to 0.998 and standard error of the estimate of 0.012 to 0.30. The predictive capability of models is evaluated for the reduced sets of calibration compounds using external test sets with ranking of the calibration models by changes in the average error, average absolute error and root mean square error of prediction for the test sets. For the selected thirty-five reduced calibration compounds the range for the average absolute error was 0.014 to 0.033 and 0.016 to 0.040 for the root mean square error of prediction for the independent test sets.

Journal of Chromatography A published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Application of 2-Methoxynaphthalene.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Poole, Colin F. published the artcileEvaluation of the solvation parameter model as a quantitative structure-retention relationship model for gas and liquid chromatography, Related Products of ethers-buliding-blocks, the publication is Journal of Chromatography A (2020), 461308, database is CAplus and MEDLINE.

The Wayne State University (WSU) exptl. descriptor database is utilized to bench mark the current capability of the solvation parameter model for use as a quant. structure-retention relationship tool for estimating retention in gas and reversed-phase liquid chromatog. The prediction error for the retention factors of varied compounds on six open-tubular columns for gas chromatog. (Rtx-5 SIL MS, DB-35 ms, RtxCLPesticides, HP-88, HP-INNOWAX and SLB-IL76) and three packed columns for reversed-phase liquid chromatog. (SunFire C₁₈, XBridge Shield RP₁₈, and XBridge Phenyl) is used to establish expectations related to current practices. Each column data set was divided into a training set for calibration and a test set for validation employing a roughly 1 to 2 split, such that each test set contained about 40 to 80 varied compounds The average absolute error for the prediction of retention factors by gas chromatog. varied from about 0.1 to 0.4 on the retention factor scale with the larger error typical of stationary phases ranked as the most polar (or cohesive). For reversed-phase liquid chromatog. the average error for the prediction of retention factors was 0.3 to 0.5 and generally larger than for gas chromatog. Statistical filters where utilized to identify a group of polycyclic aromatic compounds without hydrogen-bonding functional groups with a larger prediction error on the SunFire C₁₈ column than for other compounds of smaller size, flexible structure or containing hydrogen-bonding functional groups. The heterogeneity of the retention mechanism is speculated to be the main contribution to the prediction error for both gas and liquid chromatog. using the solvation parameter model.

Journal of Chromatography A published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Related Products of ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Poole, Colin F. published the artcileSelection of calibration compounds for selectivity evaluation of siloxane-bonded silica columns for reversed-phase liquid chromatography by the solvation parameter model, Recommanded Product: 2-Methoxynaphthalene, the publication is Journal of Chromatography A (2020), 461652, database is CAplus and MEDLINE.

For the faster evaluation of selectivity in reversed-phase liquid chromatog. of siloxane-bonded silica columns using the solvation parameter model a minimal set of calibration compounds is described suitable for mobile phase composition from 20-70% (volume/volume) methanol-, acetonitrile-, or tetrahydrofuran-water. The Kennard-Stone uniform mapping algorithm is used to select the calibration compounds from a larger database of compounds with known retention properties used earlier for column selectivity evaluation. Thirty-five compounds are shown to be necessary to minimize the standard deviation of the system constants and to minimize the difference between the system constants determined by conventional calibration and the values obtained for the reduced calibration compounds The models for SunFire C₁₈ with methanol-, acetonitrile- and tetrahydrofuran-water mobile phase compositions and XBridge Shield RP18, XBridge C₈, XBridge Ph and Discovery HS F5 with methanol- and acetonitrile-water mobile phase compositions had an average coefficient of determination of 0.996 (standard deviation = 0.003, n = 11) and average standard error of the estimate 0.025 (standard deviation = 0.005, n = 11) for the reduced calibration compounds Some octadecylsiloxane-bonded silica stationary phases with a high bonding d. and methanol-water mobile phase compositions containing ≤ 30% (volume/volume) methanol exhibit extreme retention factors (log k > 2.5) for the low-polarity, two-ring aromatic compounds in the thirty-five compound calibration set. Alternative calibration compounds with more favorable retention properties are suggested as replacements in these cases. The predictive capability of the calibration models is validated using external test sets characterized by the average error, average absolute error and root mean square error of prediction. For the thirty-five calibration compounds sets the average absolute error 0.026 (standard deviation = 0.009, n = 11) and root mean square error of prediction 0.032 (standard deviation = 0.010, n = 11) confirm the suitability of the calibration models for column selectivity evaluation. System maps for XBridge Shield RP18 for 20-70% (volume/volume) methanol-water and Synergi Hydro-RP and 50% (volume/volume) methanol-water at temperatures from 25-65°C together with a correlation diagram for XBridge Shield RP18 and SunFire C₁₈ are presented as representative applications of the reduced calibration compounds for column selectivity evaluation.

Journal of Chromatography A published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Recommanded Product: 2-Methoxynaphthalene.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem