- Development of a compound-specific carbon isotope analysis method for atmospheric formaldehyde via NaHSO3 and cysteamine derivatization
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A novel method has been developed for the compound-specific carbon isotope analysis of atmospheric formaldehyde using gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). The method allows the determination of the δ13C value for atmospheric formaldehyde at nanogram levels with higher precision and lower detection limit. In the present work, atmospheric formaldehyde was collected using NaHSO3-coated Sep-Pak silica gel cartridges, washed out by water, then derivatized by cysteamine of known δ13C value, and the δ13C value of its derivative (thiazolidine) determined by GC/C/IRMS. Finally, the δ13C value of atmospheric formaldehyde could be calculated by a simple mass balance equation between formaldehyde, cysteamine, and thiazolidine. Using three formaldehydes with different δ13C values, calibration experiments were carried out over large ranges of formaldehyde concentrations. The carbon isotope analysis method achieved excellent reproducibility and high accuracy. There was no carbon isotopic fractionation throughout the derivatization processes. The differences in the carbon isotopic compositions of thiazolidine between the measured and predicted values were always 13C values of atmospheric formaldehyde were different during the daytime and nighttime. This method proved suitable for the routine operation and may provide additional insight on sources and sinks of atmospheric formaldehyde.
- Yu,Wen,Feng,Bi,Wang,Peng,Sheng,Fu
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Read Online
- Structural determination and odor characterization of N-(2-mercaptoethyl)-1,3-thiazolidine, a new intense popcorn-like-smelling odorant
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The chemical structure of a novel, roasty, popcorn-like-smelling aroma compound formed from the reaction of fructose with cysteamine was studied by high-resolution mass spectrometry and nuclear magnetic resonance experiments. The structure of N-(2-mercaptoethyl)-1,3-thiazolidine exhibiting the extremely low odor threshold of 0.005 ng/L in air was finally confirmed by synthesis.
- Engel, Wolfgang,Schieberle, Peter
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Read Online
- Process for the preparation of teneligliptin
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A process for the preparation of teneligliptin.
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Page/Page column 24
(2017/01/02)
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- Facile synthesis of a family of H8BINOL-amine compounds and catalytic asymmetric arylzinc addition to aldehydes
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A family of optically active H8BINOL-AM compounds containing 3,3′-bis-tertiary amine substituents are synthesized by using a one-step reaction of H8BINOL with amino methanols that were in situ generated from various cyclic or acyclic secondary amines and paraformaldehyde. The H 8BINOL-AM compounds are used to catalyze the reaction of functional arylzincs, in situ prepared from the reaction of aryliodides with ZnEt 2, with aldehydes to produce chiral diaryl carbinols and a few arylalkyl carbinols. Through this study, highly enantioselective catalysts were identified. It was found that the H8BINOL-AM compounds with sterically less congested cyclic or acyclic amino methyl substituents were more enantioselective than those with more bulky substituents. The pyrrolidinyl derivative (S)-12 in most cases showed greater enantioselectivity than other H8BINOL-AM compounds, especially for the challenging ortho-substituted aromatic aldehydes. A H8BINOL-AM with 3,3′-bis-sec-amine substituents, prepared by a multistep method, was also used to catalyze the arylzinc addition to aldehydes, but it showed enantioselectivity lower than that of the compounds with tertiary amine groups. It was found for the first time that an aryl bromide, 2-bromothiophene, could be used to prepare an arylzinc reagent by reaction with ZnEt2. The addition of this heteroarylzinc reagent to an aldehyde in the presence of (S)-12 proceeded with good enantioselectivity.
- Deberardinis, Albert M.,Turlington, Mark,Ko, Jason,Sole, Laura,Pu, Lin
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experimental part
p. 2836 - 2850
(2010/08/05)
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- 2-aminopyridine derivatives and combinatorial libraries thereof
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The present invention relates to novel 2-aminopyridine derivative compounds of the following formula: wherein R1to R5have the meanings provided herein. The invention further relates to combinatorial libraries containing two or more such compounds, as well as methods of preparing 2-aminopyridine derivative compounds.
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- 14-substituted marcfortines and derivatives useful as antiparasitic agents
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There are disclosed 14α-hydroxymarcfortine derivatives of the natural products marcfortine A, B, C, and D useful in the treatment and prevention of helminth and arthropod infections of animals and plants. The synthetic derivatives are of Formula (I). STR1
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- Marcfortine/paraherquamide derivatives useful as antiparasitic agents
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There are disclosed 18-thiomarcfortine derivatives of the natural products marcfortine A, B and C, C-18 thioparaherquamide and derivatives thereof, novel N-1 marcfortines A, B, and C and derivatives thereof, novel N-1 paraherquamide and derivatives thereof usefull in the treatment and prevention of helninth and arthropod infections of animals and plants. Any inquiry concerning this communication or earlier communications from the examiner should be directed to Examiner Robert T. Bond whose telephone number is (703)308-4711. The examiner can normally be reached on Monday through Friday from 8:00 AM to 4:30 PM.
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- Scavenger assisted combinatorial process for preparing libraries of amides, carbamates and sulfonamides
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This invention relates to a novel solution phase process for the preparation of amide, carbamate, and sulfonamide combinatorial libraries. These libraries have utility for drug discovery and are used to form wellplate components of novel assay kits.
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- Mechanistic Studies on Thiazolidine Formation in Aldehyde/Cysteamine Model Systems
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A mechanism was proposed to elucidate the formation of a thiazolidine in aldehyde/cysteamine model systems. Buffer dramatically promotes thiazolidine formation from formaldehyde and cysteamine. Phosphate tends to stabilize the primary carbocation formed, and this may lead to completion of the cyclization by attack of the amino nitrogen on the activated carbon. Protic solvent, by removing the water molecule, further enhances thiazolidine formation. Redox reaction catalyzed by phosphate ions results in the conversion of thiazolidine to the corresponding thiazoline through hydride transfer.
- Huang, Tzou-Chi,Huang, Lee-Zen,Ho, Chi-Tang
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p. 224 - 227
(2007/10/03)
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- Antiatherosclerotic and antithrombotic 1-benzopyran-4-ones and 2-amino-1,3-benzoxazine-4-ones
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This invention relates to compounds of Formula I STR1 which are useful in association with a pharmaceutical carrier as antiatherosclerotic agents. In addition, various compounds of Formula I are useful inhibitors of cell proliferation.
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- β-carbonyl-carboxyamides of 1,3-thiazolidines
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This application relates to compounds of formula I; STR1 wherein R is hydrogen, a linear or branched C1 -C4 -alkyl, allyl or propargyl; X is O, CH2 or S; R1 is --(CH2)n Ra, hydroxy, --O--(CH2)n Ra, --NRbRc or --NH c(CH2)m --NRbRc; Ra is hydrogen, a linear or branched C1 -CH4 -alkyl, phenyl, p-methoxy-phenyl, 3,4,5-trimethoxyphenyl, B-pyryidyl, cyclopentyl or cyclohexyl; Rb and Rc, can be the same or different and are selected independently in the group of hydrogen, linear or branched C1 -C4 -alkyl, cyclohexyl, cyclopentyl, benzyl, hexahydrobenzyl, α,β or γ-pyridylmethyl; or Rb and Rc taken together with the N atom to which they are bound can form a morpholino, piperidino or piperazino residue of formula Rd--N(CH2 --CH2)2 --N-- wherein Rd is hydrogen, linear or branched C1 -C4 -alkyl, benzyl, hexahydrobenzyl, (C6 H5)2 CH--, (p--F--C6 H4)2 CH or B-pyridylmethyl; n is zero or an integer from 1 to 3 and m is 2 or 3; and a process for the preparation thereof.
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- Platelet activating antagonists
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Indole compounds substituted at the 1- or 3 position by a (pyrid-3 yl)thiazolid-4-yl)alkyl-, (pyrid-3-yl)thiazolid-4-oyl)-, (pyrid-3-yl)dithiolan-4-yl)alkyl- or (pyrid-3-yl) dithiolan-4-ol)- group are potent inhibitors of PAF and are useful in the treatment of PAF-related disorders including anaphylactic shock, respiratory distress syndrome, acute inflammation, delayed cellular immunity, parturtition, fetal lung maturation, and cellular differentiation.
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- Benzoylphenyl pyridinylthiazolidine compounds as platelet activating antagonists
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Benzoylphenyl derivatives of 2-(3-pyridinyl)-3-alkyl-4-thiazolidinecarboxamide, 2-(3-pyridinyl)-thiazolid-4-ylacetamide, 2-(3-pyridinyl)-4-dithiolanecarboxamide or 2-(3-pyridinyl)dithiolan-4-yl] urea are potent inhibitors of PAF and are useful in the treatment of PAF-related disorders including anaphylactic shock, respiratory distress syndrome, acute inflammation, delayed cellular immunity, parturtition, fetal lung maturation, and cellular differentiation.
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- Platelet activating antagonists
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Benzoylphenyl derivatives of 2-(3-pyridinyl)-3-alkyl-4-thiazolidinecarboxamide, 2-(3-pyridinyl)-thiazolid-4-ylacetamide, 2-(3-pyridinyl)-4-dithiolanecarboxamide or 2-(3-pyridinyl)dithiolan-4-yl]urea-group are potent inhibitors of PAF and are useful in the treatment of PAF-related disorders including anaphylactic shock, respiratory distress syndrome, acute inflammation, delayed cellular immunity, parturtition, fetal lung maturation, and cellular differentiation.
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- Iminophenylthiazolidines, process of preparation and method of use
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A 2-iminophenyl thiazolidine having the formula STR1 wherein R is hydrogen or methyl; R1 is halo, nitro, cyano, C1 -C4 alkyl, C1 -C4 alkoxy, perhalomethyl, difluoromethyl, pentafluoroethyl, trifluoromethylthhio, difluoromethoxy, trifluoromethoxy, tetrafluoroethoxy, methylsulfonyl, C1 -C4 alkyloxyiminomethyl, benzyloxyiminomethyl, 1-(C1 -C4 alkyl)-oxyiminoethyl or 1-benzyloxyiminoethyl; R2 is hydrogen or halo; R3 and R4 are independently hydrogen, halo, nitro, cyano, C1 -C4 haloalkyl, C1 -C4 alkyl, C1 -C4 fluoroalkoxy, C1 -C4 alkoxy or C1 -C4 alkylthio; and X is hydrogen or halogen. Also disclosed is a process for making the compounds and a method of use which comprises applying the compound or composition to the locus where control is desired.
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- 2-(acylimino)thiazolidine herbicides
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Herbicidal compounds have the formula STR1 in which W is oxygen or sulfur; X is hydrogen, halogen, nitro, cyano, perhalomethyl, difluoromethyl, pentafluoroethyl, C1 -C4 alkyl, C1 -C4 alkoxy, trifluoromethylthio, difluoromethoxy, trifluoromethoxy, tetrafluoroethoxy, methylsulfonyl, trifluoromethylsulfonyl, phenoxy, pyridyloxy, halo-substituted-phenoxy or -pyridyloxy, trifluoromethyl-substituted-phenoxy or -pyridyloxy, C1 -C4 alkyloximinomethyl, benzyloximinomethyl, 1-(C1 -C4 alkyl)-oximinoethyl and 1-benzyloximinoethyl; Y is hydrogen, halogen, nitro, cyano, perhalomethyl, difluoromethyl, pentafluoroethyl, C1 -C4 alkyl, C1 -C4 alkoxy, trifluoromethylthio, trifluoromethoxy, tetrafluoroethoxy, methylsulfonyl and trifluoromethylsulfonyl; Z is hydrogen or fluoro if Y is hydrogen, or hydrogen if Y is other than hydrogen; R1 is hydrogen, methyl, ethyl or chloromethyl; A is oxygen, sulfur, STR2 in which R3 and R4 are independently hydrogen, methyl or methoxy; and R2 is alkyl; carboalkoxy; carboalkoxyalkylene; haloalkyl; alkoxy; optionally methylsubstituted cycloalkyl; phenyl; substituted phenyl; phenoxy; halophenoxy; styryl; p-chlorophenylsulfonyl; haloalkylcarbonyl; napthyl; halonapthyl; benzoyl; halo-substituted benzyl; polycyclic aliphatic; mono- or dialkylamino; benzoyl; or a 5- to 6-member heterocyclic ring containing 1-2 oxygen or sulfur atoms, optionally substituted; and m is 0 or 1.
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- Thiazolidine derivatives, process for their preparation and pharmaceutical compositions
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Compounds of formula I wherein A represents:, - a saturated or unsaturated acyclic residue;, - a saturated cyclic or heterocylic residue;, - a saturated or unsaturated bicyclic residue, and R represents OH, a C1-C4 alkoxy group or a straight or heterocycle aminoresidue; R1 represents hydrogen, an alkyl group or an aromatic or heteroaromatic residue. Compounds I are endowed with valuable therapeutic characteristics.
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- Thiazolidine derivatives, process for their preparation and pharmaceutical compositions
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Compounds of formula I STR1 wherein A represents: a saturated or unsaturated acyclic residue; a saturated cyclic or heterocyclic residue; a saturated or unsaturated bicyclic residue; and R represents OH, a C1 -C4 alkoxy group or a straight or heterocycle aminoresidue; R1 represents hydrogen, an alkyl group or an aromatic or heteroaromatic residue. Compounds I are endowed with valuable therapeutic characteristics.
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- Aminoethanethiol and thiazolidine compounds
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There are disclosed certain aminoethanethiols, and salts thereof, and certain thiazolidines which are made therefrom. The compounds are useful as intermediates in the synthesis of photographic image dye-providing materials.
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- Treatment of atherosclerosis with khellin-related furochromones
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The present specification relates to the antiatherosclerotic use of khellin and related furochromones, and further provides novel antiatherogenic furochromones.
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- Antiatherosclerotic furochromones
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The present specification relates to the antiatherosclerotic use of khellin and related furochromones, and further provides novel antiatherogenic furochromones.
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- Anthelmintic 5(6)-benzene ring substituted benzimidazole-2-carbamates
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Benzene ring substituted benzimidazole-2-carbamate derivatives represented by the formula: STR1 where R is a lower alkyl group having 1 to 4 carbon atoms; STR2 is a 5, 6, 7 or 8 membered heterocyclic ring containing 1 to 2 hetero atoms; the STR3 substitution being at the 5(6)-position; and the pharmaceutically acceptable salts thereof. The compounds are useful as pesticides, particularly as anthelmintic and antifungal agents.
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