Showing papers on "Morpholine published in 1997"

Diels−Alder Reaction of 2-Amino-Substituted Furans as a Method for Preparing Substituted Anilines

Abstract: 5-Amino-2-furancarboxylic acid methyl ester undergoes a facile Diels−Alder cycloaddition with a variety of dienophiles to afford ring-opened cycloadducts that are readily dehydrated using BF3· OEt2 to give polysubstituted anilines. In each case, the cycloaddition proceeds with high regioselectivity, with the electron-withdrawing group being located ortho to the amino group. The most favorable FMO interaction is between the HOMO of the furanamine and the LUMO of the dienophile. The atomic coefficient at the ester carbon of the furan is larger than that at the amino center, and this nicely accommodates the observed regioselectivity. The [4 + 2]-cycloaddition of N-(5-nitrofuranyl)morpholine with methyl vinyl ketone affords a mixture of three phenols. One of the phenols is derived from a Diels−Alder reaction followed by nitro group ejection and subsequent aromatization. The remaining two phenols are the result of cleavage of the initially formed oxabicyclic intermediate with concomitant migration of the nitro...

Synthesis of Poly(glycolic acid-alt-l-aspartic acid) from a Morpholine-2,5-dione Derivative

Abstract: For the purpose of increasing the hydrophilicity of a polylactide, a new monomer, (3S)-3-[(benzyloxycarbonyl)methyl]morpholine-2,5-dione, was successfully polymerized. The benzyl protective group of the polymer was completely removed to give poly(glycolic acid-alt-l-aspartic acid). The structures and properties of both protected and deprotected polymers were carefully studied by NMR, GPC, and DCA. It is found that the morpholine-2,5-dione derivatives with side functional groups which have no substituent on the 6 position of the morpholine ring are much more reactive than those monomers with a substituent on the 6 position of the ring in polymerization. The resulting polymer shows promising hydrophilicity, as can be seen from the DCA result.

EFFICIENT SYNTHESIS OF α-ENAMINOPHOSPHONATES IN THE SERIES OF PIPERIDINE AND MORPHOLINE. Examples of synthetic applications

Abstract: Various α-piperidino or a-morpholino alkenylphosphonates are conveniently prepared from the related α-hetero-substituted methylphosphonates, through a Peterson olefination process, which can be easily adapted for a direct homologation of aldehydes into carboxylic acids. An efficient synthesis of α-piperidino or α-morpholino alkylphosphonates and phosphonic acids is proposed.

Thermodynamic Properties of Aqueous Morpholine and Morpholinium Chloride at Temperatures from 10 to 300 °C: Apparent Molar Volumes, Heat Capacities, and Temperature Dependence of Ionization

Abstract: Apparent molar heat capacities Cp,φ of aqueous morpholine and morpholinium chloride were determined with a Picker flow microcalorimeter at temperatures from 10 to 55 °C. The apparent molar volumes Vφ have been determined with platinum vibrating tube densitometers at temperatures from 10 to 300 °C and pressures in excess of steam saturation. Values of Vφ for morpholine approach large positive values at elevated temperatures, consistent with a lowering of the critical temperature in the solutions relative to water. The effect in aqueous morpholinium chloride is reversed, confirming the profound effect of ionic charge on the high-temperature thermodynamic properties of aqueous solutes, even for large organic molecules. Standard partial molar heat capacity functions were estimated from the high-temperature Vφ data and low-temperature values of Cp,φ using an empirical model based on the appropriate solvent density derivatives and the revised Helgeson−Kirkham−Flowers model. The results from both models are cons...

Nitrosation of Amines in Nonaqueous Solvents. 2. Solvent-Induced Mechanistic Changes

Abstract: We studied the nitrosation of amines (pyrrolidine, piperidine, diethylamine, N-methylpiperazine, N,N′-dimethylethylenediamine, and morpholine) by alkyl nitrites (2-bromoethyl nitrite or 2,2- dichloroethyl nitrite) or by N-methyl-N-nitroso-p-toluenesulfonamide (MNTS) in the solvents chloroform, acetonitrile, and dimethyl sulfoxide (DMSO). The mechanism of nitrosation by alkyl nitrites depends on the solvent: in chloroform, all the results were in keeping with formation of a hydrogen-bonded complex between the amine and alkyl nitrite being followed by rate-controlling formation of a tetrahedral intermediate T± that rapidly decomposes to afford the final products; in acetonitrile, a situation intermediate between those obtaining in chloroform and cyclohexane results in the [amine] dependence of the first-order pseudoconstant k0 being qualitatively influenced by temperature and by the identities of both the amine and the alkyl nitrite; in DMSO, the results suggest a mechanism close to the mechanism acting in water. For nitrosation by MNTS, k0 depended linearly on [amine] in all three solvents. The Grunwald-Winstein coefficients correlating the rate constants k for nitrosation by MNTS in the chloroform, acetonitrile, DMSO, dioxane, dichloromethane, and water were l = 0.12 and m = 0.29. Correlation with the Kamlet-Abboud-Taft equation confirmed that k depends largely on the dipolarity of the solvent and, to a lesser extent, its capacity for hydrogen bonding.

New routes to benzothiophenes, isothiazoles and 1,2,3-dithiazoles

Abstract: 4,5-Dichloro-1,2,3-dithiazolium chloride 1 condenses with active methylene compounds, such as malononitrile, barbituric acid and Meldrum’s acid, to give the dithiazol-5-ylidene derivatives, such as 3, 4 and 5, in modest yields. Better yields are obtained from 4-chloro-1,2,3-dithiazole-5-thione 6. Thus the thione 6 condenses with diphenyldiazomethane in a very mild version of the Barton double extrusion synthesis of hindered alkenes; this requires neither heat to extrude nitrogen nor a phosphine to abstract sulfur, to give the alkene 7 (83%) (Scheme 1). This alkene rearranges at room temperature, with loss of hydrogen chloride and sulfur, to give the benzothiophene 13 (89%) in a new thiophene ring-forming reaction (Scheme 2). The thione 6 also condenses with tetracyanoethylene oxide to give a better yield of the dicyanomethylene compound 3 (70%) (Scheme 4). Compound 3, in turn, reacts with morpholine and with chloride ions (Scheme 5) to give 3-morpholino- 19 (60%) and 3-chloro- 20 (100%) isothiazole-4,5-dicarbonitrile, in a new isothiazole ring synthesis. Mechanisms are proposed for all of these reactions.

Nitrosation of Amines in Nonaqueous Solvents. 1. Evidence of a Stepwise Mechanism

Abstract: We studied the nitrosation of piperidine, morpholine, pyrrolidine, N-methylpiperazine, N,N‘-dimethylethylenediamine and diethylamine by 2-bromoethyl nitrite, 2,2-dichloroethyl nitrite, 2,2,2-trichl...

Nucleophilic substitutions at the pyridine ring: Kinetics of the reaction of 2-chloro-3-nitro and 2-chloro-5-nitropyridines with piperidine and morpholine in methanol and benzene

Abstract: The kinetics of the reactions of 2-chloro-3-nitropyridine (ortho-like) and 5-nitro (para-like) isomer with morpholine and piperidine were studied in methanol and benzene at several amine concentrations and temperatures in the range 25–45°C. The data show that k/k ratios are less than unity in methanol. The steric hindrance in the transition state of the 3-nitro (ortho-like) isomer retards o-substitution while the stability of p-quinonoid structure of the 5-nitro (para-like) isomer favors p-substitution. In benzene, the k3-NO2/k5-NO2 ratios are greater than unity. The hydrogen bonding formation between the ammonium hydrogen and the ortho-nitro group in the transition state of 3-nitro isomer favors the o-substitution. © 1997 John Wiley & Sons, Inc.

Use of carboxyl-containing polysiloxanes in cosmetic formulations

Abstract: A cosmetic composition comprising a carboxyl-containing polysiloxane and a cosmetically acceptable auxiliary; in which the carboxyls are amidated by a compound selected from the group consisting of 2-amino-2-methyl-1-propanol, ethanolamine, morpholine and triethanolamine, and said amidation is up to 50 mol % of the carboxyls.

Triethylenediamine synthesis with base-treated zeolites as catalysts

Abstract: A process for preparing triethylenediamine by passing an ethanolamine, ethyleneamine, piperaziHe or morpholine over a pentasil-type zeolite at elevated temperature characterized by employing a ZSM-5 zeolite in the hydrogen or ammonium form which has been pretreated with an aqueous caustic solution.

Synthesis and pharmacokinetic behaviour of ester derivatives of 4-isobutylphenyl-2-propionic acid (Ibuprofen) with end-hydroxylated poly(N-vinyl pyrrolidinone) and poly(N-acryloyl morpholine) oligomers

Abstract: Four derivatives of 4-isobutylphenyl-2-propionic acid (Ibuprofen), in which the drug was bound by ester linkages to poly(ethylene glycols) (PEG 2000-I), monomethoxy poly(ethylene glycols) (PEG 1900-I), poly(N-vinyl pyrrolidinone) (PVP-I) and poly(N-acryloyl morpholine) (PACM-I), all having approximatively the same number average molecular weight (Mn congruent equal to 2000), were prepared and tested for their pharmacokinetic properties after oral administration. It was found that the two end-hydroxylated amphiphilic oligomers of polyvinylic structure, PACM and PVP, whose physico-chemical properties are comparable to those of PEGs especially as regards solvent affinity, have in principle a similar potential as promoieties for preparing oligomeric prodrugs.

Dietary secondary amines and liver hepatoma in Port Harcourt, Nigeria.

Abstract: Dietary secondary amines of some Nigerian foodstuffs were analyzed by Soxhlet extraction, using petroleum ether (b.p. 60–80 °C); followed by thin layer chromatography developed in a solvent system; n-butanol: 95% ethanol: water (4:2:1) for the qualitative test. Each UV fluorescent band in the test chromatogram was scraped and eluted with distilled water, filtered and assayed for secondary amine content for the quantitative test. Quantitative estimations were by the colorimetric methods. The results show that Ugu – Telfairia occidentalo; millet-Panicum miliaceum; bitter leaf – Vernonia amygdalina; mushroom – Boletus spp; and Okro – Hibiscus esculentus contain diethylamine, dimethylamine, morpholine and ethylaniline. Garri – Manihot utilissima flour contains diethylamine and dimethylamine only; while fish (frozen) Tilapia malanopleura contains diethylamine, dimethylamine and piperidine and the smoked fish – Tilapia nilotica contains diethylamine, dimethylamine, ethylaniline, morpholine, piperidine and n-propylamine. Cocoyam – Xanthosoma sagittifolium contains diethylamine, dimethylamine, morpholine, ethylaniline and proline. The results also show that the secondary amine content of the various foodstuffs ranged between 0.80–0.91 µg N/kg. The public health implications of these findings are discussed.

Synthesis of 24-(Piperidin-1-yl, Morpholin-4-yl and 4-Methylpiperazin-1-yl)-5β-cholan-3α-ols and Four Hydroxylated 23-(4,5-Dihydroimidazol-2-yl)-24-nor-5β-cholanes

Abstract: Lithocholic ( 1a ), chenodeoxycholic ( 1b ), deoxycholic ( 1c ) and cholic acid ( 1d ) were used for the synthesis of the title compouds. Reactions of O -acetyllithocholic acid chloride with piperidine, morpholine and 1-methylpiperazine gave the corresponding amides 2a-2c which were reduced with lithium aluminium hydride to 24-(piperidin-1-yl)-5β-cholan-3α-ol ( 3a ) and analogues 3b and 3c . Heating of the acids 1a-1d with ethylenediamine monotosylate afforded 23-(4,5-dihydroimidazol-2-yl)-24-nor-5β-cholan-3α-ol ( 4a ) and analogues 4b-4d . Compound 4a was similarly obtained from 3α-acetoxy-24-nor-5β-cholane-23-carbonitrile. Identity of the products was corroborated by spectral characterization. Some of the products (in the form of salts) were tested for cancerostatic and antimicrobial activities in vitro with partially promising results.

Synthesis, Structural Characterization, and Biological Activity of Two Different Nickel(II)Complexes Derived from N'-[1-(2-pyridyl)ethylidene]morpholine-4-carbothiohydrazide

Abstract: The reaction of Ni(OAc)2 with N′-[1-(2-pyridyl)ethylidene]morpholine-4-carbothiohydrazide (HL) afforded two nickel(II) complexes, [Ni(L)2] (1) and [Ni(L)(OAc)] (2), depending on reaction temperature and starting molar ratio; the former was a 6-coordinate, paramagnetic complex and the latter a 4-coordinate, diamagnetic complex. X-ray analysis of the complex 2 revealed that the ligands, L and OAc, were coordinated to the central metal ion to form a square-planar geometry. The complex 2 showed enhanced antimicrobial activities against selected Gram-positive bacteria, compared with those of the ligand alone, whereas the other complex 1 showed no activity.

4-alkyl and aryl semicarbazides as oxygen scavengers

Abstract: A method for removing dissolved oxygen from alkaline water containing dissolved oxygen at a temperature greater than 250° F. which comprises the step of: adding to said alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble semicarbazide of the formula ##STR1## wherein R1 and R2 are selected from the group consisting of C1 -C10 alkyl, cycloalkyl, aryl, cycloalkyloxy and alkyloxy groups. Preferred materials are 4-phenyl semicarbazide, 4-isopropyl semicarbazide, 4-4-diethyl semicarbazide and carbazoyl morpholine. Below 400° F., a catalyst is also required.

Diels-Alder Reaction of 2-Amino-Substituted Furans as a Method for Preparing Substituted Anilines.

Abstract: 5-Amino-2-furancarboxylic acid methyl ester undergoes a facile Diels−Alder cycloaddition with a variety of dienophiles to afford ring-opened cycloadducts that are readily dehydrated using BF3· OEt2 to give polysubstituted anilines. In each case, the cycloaddition proceeds with high regioselectivity, with the electron-withdrawing group being located ortho to the amino group. The most favorable FMO interaction is between the HOMO of the furanamine and the LUMO of the dienophile. The atomic coefficient at the ester carbon of the furan is larger than that at the amino center, and this nicely accommodates the observed regioselectivity. The [4 + 2]-cycloaddition of N-(5-nitrofuranyl)morpholine with methyl vinyl ketone affords a mixture of three phenols. One of the phenols is derived from a Diels−Alder reaction followed by nitro group ejection and subsequent aromatization. The remaining two phenols are the result of cleavage of the initially formed oxabicyclic intermediate with concomitant migration of the nitro...

SYNTHESIS AND REACTIONS OF NEW TRIAZINO THIADIAZINO AND PYRIMIDO THIENO[2,3-b]-QUINOXALINE

Abstract: 3-Amino-2-carbamoylthieno[2,3-b]quinoxaline 3 was synthesized and allowed to react with chloroacetyl chloride to give N-chloroacetyl derivative 4. Cyclization of 4 into the title compund 5 was achieved in boiling acetic anhydride. Reactions of 5 with morpholine and diethylamine afforded pyrimidinones 6 and 7. Reaction of 3 with sulfuryl chloride, thionyl chloride and nitrous acid gave thiadiazine derviatives 8 and 9 and triazinothienoquinoxaline 11. Thionation and chlorination of 11 by P2S5 and/or POCl3 gave thioxotriazino and chlorotriazinothiencquinoxalines 12 and 13, respectively. Treatment of either 12 or 13 with hydrazine hydrate afford the hydrazinotriazinoquinoxaline 14 which was utilized as precursor for producing other new triazinothiencquinoxalines 15–17.

Benzothiophenes, formulations containing same, and methods for their préparation

Abstract: of EP0791591This invention provides pharmaceutical benzothiophene compounds of the formula wherein R is hydrogen, hydroxy, C1-C4 alkoxy, wherein Ar is optionally substituted phenyl, or -SO2(C4-C6 straight chain alkyl); R is R , Cl or F; and R and R are, independently, C1-C4 alkyl or combine to form a C4-C6 polymethylene or, together with the nitrogen to which they are attached form morpholine, X is -CH2, -CHOH2-, -O-, or or a pharmaceutically acceptable salt or solvate thereof. s