Tag: M.W=150-200

Fujimoto, Yoshinori published the artcileSteroids. XXIX. Synthesis of allenic analogs of fucosterol and desmosterol, Application of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) (1975), 2302-7, database is CAplus.

Reaction of 24-oxocholesterol tetrahydropyranyl (Thp) ether with NaCCH in NH3(l) gave the 24-ethynyl alc. which was acetylated. Reduction of the acetate with LiAlH4-AlCl3 (3:1) in THF gave the fucosterol allenic analog I [R = CH2C(CHMe2):C:CH2]. Coupling of 22-tolylsulfonyloxy-23,24-bisnorchol-5-en-3β-yl Thp ether with CHCCMe2OH Thp ether followed by hydrolysis gave cholest-5-en-23-yne-3β,25-diol. Treatment of the above diol with LiAlH4-AlCl3 gave the desmosterol allenic analog I (R = CH:C:CMe2).

Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) 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, Application of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran.

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

Bolitt, Veronique published the artcileTriphenylphosphine hydrobromide: a mild and efficient catalyst for tetrahydropyranylation of tertiary alcohols, Category: tetrahydropyran, the publication is Tetrahedron Letters (1988), 29(36), 4583-6, database is CAplus.

PPh₃.HBr is a convenient and highly effective catalyst for tetrahydropyranylation of tertiary alcs. with dihydropyran in CH₂Cl₂ at ambient temperature Thus EtMe₂COH gave 92% tetrahydropyranyl ether.

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, Category: tetrahydropyran.

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

Hetru, C. published the artcileSynthesis of high specific activity (23,24)-³H₄-2-deoxyecdysone, Quality Control of 27943-46-0, the publication is Nouveau Journal de Chimie (1983), 7(10), 587-91, database is CAplus.

Deoxyecdysone I (R = H) was prepared from ergosterol via alkynylation of pregnenecarboxaldehyde II with R¹OCMe₂CCMgBr (R¹ = tetrahydro-2H-pyran-2-yl) to give cholestenynones III. Reduction of cholestenyne IV by tritium in MeOH containing Pd/C and NaNO₂ gave I (R = T) with a specific activity of 108 Ci/mmole. I (R = H) has biolog. activity similar to that of ecdysone and is metabolized to ecdysone and 20-hydroxyecdysone by insects.

Nouveau Journal de Chimie 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, Quality Control 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

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

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

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

Journet, Michel published the artcileRadical cyclization of (bromomethyl)dimethylsilyl propargyl ethers. Regio-, chemo- and stereoselectivity., Related Products of tetrahydropyran, the publication is Journal of Organic Chemistry (1992), 57(11), 3085-93, database is CAplus.

Radical cyclization of (bromomethyl)dimethylsilyl propargyl ether derivatives I [R¹ = R² = Me, R³ = (CH₂)_nCH:CH₂, n = 1,2,4, (CH₂)₃OTHP, Ph, SiMe₃; R¹ = H, R² = R³ = Bu; R¹ = R³ = H, R² = H, Me; R¹ = R² = H, R³ = pentyl; R¹ = H, R² = Me, R³ = Ph, pentyl] is a powerful reaction with a high degree of regio-, chemo-, and stereoselectivity. Trisubstituted olefins II (R⁴ = H, OH, SiMe₃), cyclopentene derivatives III, and diquinane system IV are obtained in good yields by a judicious choice of unsaturated substituents. Triquinane frameworks could be obtained stereoselectively from a suitable acyclic substrate of type I in a one-pot reaction. First attempts have not yet allowed us to aim at this goal due to interesting (1,5) hydrogen transfers. Moreover, intercepted, for the first time, is the α-cyclopropyl radical which is involved in the Stork-Beckwith mechanism of the 5- vs. 6-membered ring formation in the vinyl radical cyclization.

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, Related Products of tetrahydropyran.

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

Naapuri, Janne M. published the artcileCascade Catalysis Through Bifunctional Lipase Metal Biohybrids for the Synthesis of Enantioenriched O-Heterocycles from Allenes, HPLC of Formula: 27943-46-0, the publication is ChemCatChem, database is CAplus.

Lipase/metal nanobiohybrids, generated by growth of silver or gold nanoparticles on protein matrixes are used as highly effective dual-activity heterogeneous catalysts for the production of enantiomerically enriched 2,5-dihydrofurans (R)-I [R¹ = Me, Et; R²₂ = (CH₂)₅; R³ = R⁴ = H] from allenic acetates II (X = MeCO) in a one-pot cascade process combining a lipase-mediated hydrolytic kinetic resolution with a metal-catalyzed allene cycloisomerization. Incorporating a novel strategy based on enzyme-polymer bioconjugates in the nanobiohybrid preparation enables excellent conversions in the process. Candida antarctica lipase B (CALB) in combination with a dextran-based polymer modifier (DexAsp) proved to be most efficient when merged with silver nanoparticles. A range of hybrid materials were produced, combining Ag or Au metals with Thermomyces lanuginosus lipase (TLL) or CALB and its DexAsp or polyethyleneimine polymer bioconjugates. The wider applicability of the biohybrids is demonstrated by their use in cyclization of allenic alcs. II [X = H; R¹ = Me, Et, Ph, etc., R³ = H; R¹ = Me, R³ = Ph; R¹R³ = (CH₂)₅; R² = Me, R²₂ = (CH₂)₅; R⁴ = H; R¹R⁴ = (CH₂)₄], where a variety of dihydrofurans I is obtained using a CALB/gold nanomaterial. These results underline the potential of the nanobiohybrid catalysis as promising approach to intricate one-pot synthetic strategies.

ChemCatChem 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, HPLC of Formula: 27943-46-0.

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

Larock, Richard C. published the artcileMercury in organic chemistry. 24. Mercuration and subsequent carbonylation of 4-hydroxy-2-alkyn-1-ones: a novel route to furans, Safety of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Journal of Organic Chemistry (1983), 48(13), 2151-8, database is CAplus.

HgCl₂ readily adds to the CC bond of certain 4-hydroxy-2-alkyn-1-ones (e.g., HOCHMeCCAc) to give vinylmercurials [e.g., HOCHMeCCl:C(HgCl)COMe] which appear to be the 1st syn-addition compounds of HgCl₂. These vinylmcercurials readily dehydrate to 3-furylmercurials (e.g., I). Pd-promoted carbonylation of these compounds affords 3-furylcarbonyl compounds

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, 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