Category: tetrahydropyran

Draganov, Dragomir I. published the artcileExtensive metabolism and route-dependent pharmacokinetics of bisphenol A (BPA) in neonatal mice following oral or subcutaneous administration, Computed Properties of 267244-08-6, the publication is Toxicology (2015), 168-178, database is CAplus and MEDLINE.

Orally administered bisphenol A (BPA) undergoes efficient first-pass metabolism to produce the inactive conjugates BPA-glucuronide (BPA-G) and BPA-sulfate (BPA-S). This study was conducted to evaluate the pharmacokinetics of BPA, BPA-G and BPA-S in neonatal mice following the administration of a single oral or s.c. (SC) dose. This study consisted of 3 phases: mass-balance phase in which ED delivery procedures for oral or SC administration of ³H-BPA to postnatal day three (PND3) mice were developed; pharmacokinetic phase during which systemic exposure to total ³H-BPA-derived radioactivity in female PND3 mice was established; and metabolite profiling phase in which 50 female PND3 pups received either a single oral or SC dose of ³H-BPA. Blood was collected from 5 pups/route/time-point at various times post-dosing, the blood plasma samples were pooled by group, and time-point and samples were profiled by HPLC with fraction collection. Fractions were analyzed for total radioactivity and data used to reconstruct radiochromatograms and to integrate individual peaks. The identity of the BPA, BPA-G, and BPA-S peaks was confirmed using authentic standards and LC-MS/MS anal. The result of this study revealed that female PND3 mice have the capacity to metabolize BPA to BPA-G, BPA-S and other metabolites after both routes of administration. Systemic exposure to free BPA is route-dependent as the plasma concentrations were lower following oral administration compared to SC injection.

Toxicology published new progress about 267244-08-6. 267244-08-6 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Chiral,Carboxylic acid,Benzene,Phenol,Alcohol,Ether,, name is (2S,3S,4S,5R,6S)-3,4,5-Trihydroxy-6-(4-(2-(4-hydroxyphenyl)propan-2-yl)phenoxy)tetrahydro-2H-pyran-2-carboxylic acid, and the molecular formula is C21H24O8, Computed Properties of 267244-08-6.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Conrads, Martin published the artcileCycloadditions. 32. Convenient methods for the preparation of sulfur substituted allenecarboxylates, COA of Formula: C10H16O2, the publication is Synthesis (1991), 11-14, database is CAplus.

2-Sulfinyl- and 2-sulfonylallenecarboxylates, as new 1,1-diacceptor substituted allenes, were prepared starting from Me 4-hydroxy-4-methyl-2-pentynoate by a [2,3]-sigmatropic rearrangement. The sulfoxides could be reduced to the corresponding allenyl sulfides. A 2(5H)-furanone derivative was prepared by a side reaction.

Synthesis published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, COA of Formula: C10H16O2.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Baroudi, Abdulkader published the artcileConformationally Gated Fragmentations and Rearrangements Promoted by Interception of the Bergman Cyclization through Intramolecular H-Abstraction: A Possible Mechanism of Auto-Resistance to Natural Enediyne Antibiotics?, Safety of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Journal of the American Chemical Society (2010), 132(3), 967-979, database is CAplus and MEDLINE.

A variety of fragmentations and rearrangements can follow Bergman cyclization in enediynes equipped with acetal rings mimicking the carbohydrate moiety of natural enediyne antibiotics of the esperamicin and calicheamicin families. In the first step of all these processes, intramol. H-atom abstraction efficiently intercepts the p-benzyne product of the Bergman cyclization through a six-membered TS and transforms the p-benzyne into a new more stable radical. Depending on the substitution pattern and reaction conditions, this radical follows four alternative paths: (a) abstraction of an external hydrogen atom, (b) O-neophyl rearrangement which transposes O- and C-atoms of the substituent, (c) fragmentation of the O-C bond in the acetal ring, or (d) fragmentation with elimination of the appended acetal moiety as a whole. Experiments with varying concentrations of external H-atom donor (1,4-cyclohexadiene) were performed to gain further insight into the competition between intermol. H-abstraction and the fragmentations. The Thorpe-Ingold effect in gem-di-Me substituted enediynes enhances the efficiency of fragmentation to the extent where it cannot be prevented even by a large excess of external H-atom donor. These processes provide insight into a possible mechanism of unusual fragmentation of esperamicin A₁ upon its Bergman cycloaromatization and lay foundation for a new approach for the conformational control of reactivity of these natural antitumor antibiotics. Such an approach, in conjunction with supramol. constraints, may provide a plausible mechanism for resistance to enediyne antibiotics by the enediyne-producing microorganisms.

Journal of the American Chemical Society published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Safety of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Kessberg, Anton published the artcileEnantioselective Synthesis of 2′- and 3′-Substituted Natural Flavans by Domino Asymmetric Transfer Hydrogenation/Deoxygenation, Recommanded Product: 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, the publication is Organic Letters (2016), 18(24), 6500-6503, database is CAplus and MEDLINE.

A concise and highly enantioselective synthesis of the natural flavans kazinol U and (2S)-7,3′-dihydroxy-4′-methoxyflavan is reported for the first time. The key transformation is a single-step conversion of a racemic flavanone to a flavan by means of an asym. transfer hydrogenation/deoxygenation cascade with kinetic resolution

Organic Letters published new progress about 69097-99-0. 69097-99-0 belongs to tetrahydropyran, auxiliary class Other Aliphatic Heterocyclic,Benzene,Phenol,Ether,Inhibitor, name is 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, and the molecular formula is C16H14O6, Recommanded Product: 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Kurek-Tyrlik, Alicja published the artcileSynthesis of 17-epi-Calcitriol from a Common Androstane Derivative, Involving the Ring B Photochemical Opening and the Intermediate Triene Ozonolysis, Synthetic Route of 27943-46-0, the publication is Journal of Organic Chemistry (2005), 70(21), 8513-8521, database is CAplus and MEDLINE.

An efficient synthesis of 17-epi-calcitriol (I), an epimer of natural hormone, via 17-epi-cholesterol II is described. Synthesis of II includes palladium-catalyzed cyclopropanation of the common androstane derivative III with an alkyl diazoacetate, reductive fission of the less shielded side of cyclopropane carboxylic acid esters, oxidation of the products into acid, and alkylation of ester. Photolysis of 7,8-dehydro-17-epi-25-hydroxycholesterol and consecutive thermal rearrangement gave a mixture of several products that was subjected to ozonolysis to provide, after chromatog., hydroxy ketone IV. The silyl derivative of IV was coupled with the resp. ring A building block.

Journal of Organic Chemistry published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Synthetic Route of 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Kurek-Tyrlik, Alicja published the artcileA synthesis of 17-epi-calcidiol, Related Products of tetrahydropyran, the publication is Tetrahedron Letters (2004), 45(40), 7479-7482, database is CAplus.

The first synthetic approach to 17-epi-calcidiol (I) and congeners is presented. Key steps of the synthesis involve Pd-catalyzed reaction of the androst-16-ene derivative II with alkyl diazoacetates producing the resp. 16,17-cyclopropano derivatives, and lithium in liquid ammonia reduction leading to 17α-pregnane-20-carboxylic acid derivatives The side chain was attached in a known manner.

Tetrahedron Letters published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Related Products of tetrahydropyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Radchenko, Dmytro S. published the artcileAn easy synthesis of α-trifluoromethyl-amines from aldehydes or ketones using the Ruppert-Prakash reagent, Application In Synthesis of 1354961-50-4, the publication is Tetrahedron Letters (2013), 54(14), 1897-1898, database is CAplus.

A small library of structurally diverse primary amines bearing a geminal CF₃ group was synthesized on a preparative scale. The synthesis starts with an aldehyde or ketone that reacts with benzylamine yielding the corresponding imine. The latter is then trifluoromethylated with Me₃SiCF₃ under acidic conditions to give a benzylalkylamine. In the last step the Pd-mediated hydrogenation of the benzylalkylamines furnishes the title compounds All synthetic steps are high-yielding; neither the isolation of the intermediates nor the chromatog. purification of the products is necessary.

Tetrahedron Letters published new progress about 1354961-50-4. 1354961-50-4 belongs to tetrahydropyran, auxiliary class Trifluoromethyl,Tetrahydropyran,Fluoride,Salt,Amine, name is 4-(Trifluoromethyl)tetrahydro-2H-pyran-4-amine hydrochloride, and the molecular formula is C6H11ClF3NO, Application In Synthesis of 1354961-50-4.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Liao, Chunyang published the artcileDetermination of Free and Conjugated Forms of Bisphenol A in Human Urine and Serum by Liquid Chromatography-Tandem Mass Spectrometry, Computed Properties of 267244-08-6, the publication is Environmental Science & Technology (2012), 46(9), 5003-5009, database is CAplus and MEDLINE.

Exposure of humans to bisphenol A (BPA), a widely used industrial chem., is well-known. In humans and animals, conjugation of BPA mol. with glucuronide or sulfate is considered as a mechanism for detoxification. Nevertheless, very few studies have directly measured free, conjugated (e.g., glucuronidated), and substituted (e.g., chlorinated) forms of BPA in human specimens. In this study, free, conjugated (BPA glucuronide or BPAG and BPA disulfate or BPADS), and substituted (chlorinated BPA; mono- [BPAMC], di-[BPADC], and trichloride [BPATrC]) forms of BPA were determined in human urine and serum samples, using solid-phase extraction (SPE) and liquid chromatog.-tandem mass spectrometry (LC-MS/MS) techniques. The instrumental calibration for each of the target compounds ranged from 0.01 to 100 ng/mL and showed excellent linearity (r > 0.99). The limits of quantification (LOQs) were 0.01 ng/mL for free BPA and 0.05 ng/mL for the conjugated and substituted BPA. Resp. recoveries of the six target compounds spiked into water blanks and sample matrixes (urine and serum), and passed through the entire anal. procedure, were 96 ± 14% and 105 ± 18% (mean ± SD) for urine samples and 87 ± 8% and 80 ± 13% for serum samples. The optimal recoveries of BPAG and BPADS in the anal. procedure indicted that no deconjugation occurred during the SPE procedure. The method was applied to measure six target chems. in urine and serum samples collected from volunteers in Albany, New York. BPA and its derivatives were found in urine samples at concentrations ranging from < LOQ to a few tens of ng/mL. In serum, free and conjugated BPA were detected at sub ng/mL concentrations, whereas BPA chlorides were not detected. The urine and serum samples were also analyzed by enzymic deconjugation and liquid-liquid extraction (LLE) for the determination of total BPA, and the results were compared with those measured by the SPE method. To our knowledge, this is the first report on the occurrence of BPAG and BPADS in human serum.

Environmental Science & Technology published new progress about 267244-08-6. 267244-08-6 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Chiral,Carboxylic acid,Benzene,Phenol,Alcohol,Ether,, name is (2S,3S,4S,5R,6S)-3,4,5-Trihydroxy-6-(4-(2-(4-hydroxyphenyl)propan-2-yl)phenoxy)tetrahydro-2H-pyran-2-carboxylic acid, and the molecular formula is C21H24O8, Computed Properties of 267244-08-6.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Veiga-Lopez, Almudena published the artcileGender-specific effects on gestational length and birth weight by early pregnancy BPA exposure, Synthetic Route of 267244-08-6, the publication is Journal of Clinical Endocrinology and Metabolism (2015), 100(11), E1394-E1403, database is CAplus and MEDLINE.

Context and Objective: Effects of prenatal exposure to bisphenol A (BPA) on gestational and birth outcomes are controversial. The aim of the study was to evaluate the relationship between prenatal exposure to BPA and birth and gestational outcomes. Design, Setting, Participants, and Outcome: Levels of unconjugated (uBPA) and BPA glucuronide in 80 matching samples of pregnant women during the first trimester of pregnancy and at delivery and matching term cord blood obtained from a prospective study conducted at the University of Michigan Hospitals were determined using a methodol. validated in the National Institutes of Environmental Health Sciences funded Round Robin study and related to pregnancy outcomes. Results: Highest levels of uBPA were found in maternal term samples followed by first trimester maternal (M1) samples and cord blood. A 2-fold increase in M1 uBPA was associated with 55-g less birth weight when male and female pregnancies were combined and 183-g less birth weight with only female pregnancies. A 2-fold increase in maternal term uBPA was associated with an increased gestational length of 0.7 days for all pregnancies and 1.1 days for only female pregnancies. Conclusion: Higher uBPA exposure levels during first trimester and term are associated with sex-specific reduction in birth weight and increase in gestational length, resp. Race, parity, and employment have an effect on BPA exposure. Because low birth weight is associated with adverse health outcomes, effect of early pregnancy BPA levels on reducing birth weight highlights the risk posed by developmental exposure to BPA.

Journal of Clinical Endocrinology and Metabolism published new progress about 267244-08-6. 267244-08-6 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Chiral,Carboxylic acid,Benzene,Phenol,Alcohol,Ether,, name is (2S,3S,4S,5R,6S)-3,4,5-Trihydroxy-6-(4-(2-(4-hydroxyphenyl)propan-2-yl)phenoxy)tetrahydro-2H-pyran-2-carboxylic acid, and the molecular formula is C10H9IO4, Synthetic Route of 267244-08-6.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Tsunekawa, Ryuji published the artcileSynthesis of 5-Hydroxy-3′,4′,7-trimethoxyflavone and Related Compounds and Elucidation of Their Reversal Effects on BCRP/ABCG2-Mediated Anticancer Drug Resistance, Formula: C16H14O6, the publication is ChemBioChem (2019), 20(2), 210-220, database is CAplus and MEDLINE.

3′,4′,7-Trimethoxyflavone (TMF) has been reported to show a potent reversal effect on drug resistance mediated by breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2). In this study, we designed and synthesized five derivatives with either a hydroxy group or a fluorine atom at C-5 and several kinds of capping moiety at the C-7 hydroxy group, on the same 3′,4′-dimethoxy-substituted flavone skeleton. We subsequently evaluated the efficacies of these compounds against BCRP-expressing human leukemia K562/BCRP cells. Reversal of drug resistance was expressed as the concentration of compound causing a twofold reduction in drug sensitivity (RI50). Of the synthesized compounds, the reversal effect of 5-hydroxy-3′,4′,7-trimethoxyflavone (HTMF, RI50 7.2 nM) towards 7-ethyl-10-hydroxycamptothecin (SN-38) was stronger than that of TMF (RI50 18 nM). Fluoro-substituted 5-fluoro-3′,4′,7-trimethoxyflavone (FTMF, RI50 25 nM) and monoglycosylated 7-(β-glucosyloxy)-5-hydroxy-3′,4′-dimethoxyflavone (GOHDMF, 91 nM) also exhibited reversal effects, whereas the di- and triglycoside derivatives did not. TMF, HTMF and FTMF at 0.01-10 μM upregulated the K562/BCRP cellular accumulation of Hoechst 33342 nuclear staining dye. HTMF showed the strongest inhibition of BCRP-mediated efflux and suppression of BCRP expression of the three effective synthesized flavones.

ChemBioChem published new progress about 69097-99-0. 69097-99-0 belongs to tetrahydropyran, auxiliary class Other Aliphatic Heterocyclic,Benzene,Phenol,Ether,Inhibitor, name is 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, and the molecular formula is C6H13NO2, Formula: C16H14O6.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics