Tag: M.W=200-250

Padwa, Albert published the artcileSynthetic approaches toward the bi(2H-azirine) system, Category: bromides-buliding-blocks, the publication is Journal of Organic Chemistry (1979), 44(19), 3281-7, database is CAplus.

Three different approaches toward the synthesis of the bis(2H-azirine) system (I) were investigated. The 1st route is based on a modified Neber reaction in which the bis(trimethylhydrazonium) salt of 2,3-dimethyl-1,4-diphenyl-1,4-butanedione was treated with base. No indication of any bis(2H-azirine) could be detected in this reaction. In a 2nd approach, the reaction of 2-styryl-3-phenyl-2H-azirine with iodine azide was investigated. The major product isolated from this reaction was 1-phenyl-5-(1-azidocinnamyl)tetrazole. Subsequent studies with model systems showed that the reaction of IN₃ with 3-phenyl-2-substituted 2H-azirine gives azidotetrazoles in moderate yield. The reaction involves the addition of IN₃ across the CN double bond followed by ring opening of a transient iodoaziridine. Attack of azide on the incipient carbonium ion followed by electrocyclization of the azidoimine formed readily accommodates the formation of the tetrazole ring. The 3rd approach used for the synthesis of the bis(2H-azirine) system involved an attempt to dimerize 2-chloro-2H-azirines with activated metals or by electrolysis. 2-Chloro-2-methyl-2-phenyl-2H-azirine rearranges to the isomeric 2-chloro-3-methyl-2-phenyl-2H-azirine in solution This rearrangement is consistent with the intermediacy of an azacyclopropenyl ion chloride pair. All attempts at dimerization proved unsuccessful.

Journal of Organic Chemistry published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Apsel, Beth published the artcileTargeted polypharmacology: discovery of dual inhibitors of tyrosine and phosphoinositide kinases, SDS of cas: 849062-12-0, the publication is Nature Chemical Biology (2008), 4(11), 691-699, database is CAplus and MEDLINE.

The clin. success of multitargeted kinase inhibitors has stimulated efforts to identify promiscuous drugs with optimal selectivity profiles. It remains unclear to what extent such drugs can be rationally designed, particularly for combinations of targets that are structurally divergent. Here we report the systematic discovery of mols. that potently inhibit both tyrosine kinases and phosphatidylinositol-3-OH kinases, two protein families that are among the most intensely pursued cancer drug targets. Through iterative chem. synthesis, X-ray crystallog. and kinome-level biochem. profiling, we identified compounds that inhibit a spectrum of new target combinations in these two families. Crystal structures revealed that the dual selectivity of these mols. is controlled by a hydrophobic pocket conserved in both enzyme classes and accessible through a rotatable bond in the drug skeleton. We show that compound I blocks the proliferation of tumor cells by direct inhibition of oncogenic tyrosine kinases and phosphatidylinositol-3-OH kinases. These mols. demonstrate the feasibility of accessing a chem. space that intersects two families of oncogenes.

Nature Chemical Biology published new progress about 849062-12-0. 849062-12-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronic Acids,Boronic acid and ester, name is (3-Bromo-5-methoxyphenyl)boronic acid, and the molecular formula is C7H8BBrO3, SDS of cas: 849062-12-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Negishi, Eiichi published the artcileNovel silicon-promoted cycloalkylation of alkenylmetal derivatives, Category: bromides-buliding-blocks, the publication is Journal of the American Chemical Society (1983), 105(20), 6344-6, database is CAplus.

Two novel cycloalkylation reactions of alkenylmetals, in which Si plays subtle but critical roles, are described. Such cycloalkylation reactions appear to be unprecedented. Significantly, neither appears to be affected by the stereochem. integrity of alkenylmetal intermediates. Together, they provide novel and convenient routes to cycloalkenylsilanes. X(CH₂)₂CCSiMe₃ (I, X = C, Br, I) are either hydroaluminated with diisobutylaluminum hydride or carboaluminated with Me₃Al-Cl₂ZrCp₂ in nonpolar solvents, such as hexane, benzene or (CH₂Cl)₂, and were converted into 1-trimethylsilyl-1-cyclobutene and its derivatives in 80-100% yields. The available data suggest that the reaction involves a π-type process via cyclopropylcarbinyl cationic series. A similar reaction occurs with 1-trimethylsilylpropargyl bromide. Its reaction with Me₃Al-Cl₂ZrCp₂ gives II instead of III. Application of the method to the preparation of five- and six-membered alkenylsilanes have not been successful. Fortunately, an alternate procedure was developed which presumably involves a σ-type process. Thus, treatment of appropriate ω-bromo-1-trimethylsilyl-1-iodo-1-alkenes with 2 equivalent of Me₃CLi in ether at -78° followed by gradual warming has produced 1-trimethyl-1-cycloalkenes containing four-, five-, and six-membered rings in 64-81% yields. The synthetic utility of these cyclization reactions may be indicated by a 4-step conversion of I to grandisol (IV) as a 2:1 mixture of the Z and E isomers in overall 40% yield.

Journal of the American Chemical Society published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Negishi, Eiichi published the artcileMetal promoted cyclization. 18. Novel cycloalkylation reactions of (ω-halo-1-alkenyl)metal derivatives. Synthetic scope and mechanism, SDS of cas: 69361-41-7, the publication is Journal of the American Chemical Society (1988), 110(16), 5383-96, database is CAplus.

(ω-Haloalkenyl)metals undergo both σ- and π-type cyclization reactions. The σ-cycloalkylation reaction, which has so far been observed only with alkenyllithiums, provides 3- through 7-membered rings in high yields. It requires the cis relationship between Li and the ω-haloalkyl group in the cyclization step. The presence of a trialkylsilyl group on the Li-bearing C atom facilitates configurational isomerization. However, it is not necessary for cyclization. The reaction proceeds with retention of regiochem. The cycloalkylation reactions of (ω-halo-1-silyl-1-alkenyl)metals containing Al, Zn, Zr, or Si, on the other hand, proceed via π-type cyclization processes. Thus, cyclization of X(CH₂)₂CMe:C(SiMe₃)(AlMe₂), prepared by the reaction of X(CH₂)₂CCSiMe₃ (X = Cl, Br, iodo, 4-MeC₆H₄SO₂) with Me₃Al in presence of (η⁵-C₅H₅)₂ZrCl₂ in CH₂Cl₂, gave 2-methyl-1-(trimethylsilyl)cyclobutene. The relative ease of ring formation with respect to ring size is 3 and 4 ≫ 5 < 6. Formation of cyclobutenylsilanes is nonregiospecific. The stereochem. of alkenylmetal intermediates is unimportant, but the presence of a silyl group as the second metal group is necessary. The reaction can be inhibited by some polar solvents, such as THF. All of these facts can be accommodated by π-cyclization mechanisms and Baldwin’s cyclization rules.

Journal of the American Chemical Society published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, SDS of cas: 69361-41-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Arbuzov, B. A. published the artcileReaction of some chloro and bromo derivatives with sodium diethyl phosphite, Formula: C6H12Br2, the publication is Sbornik Statei po Obshchei Khimii (1953), 1144-8, database is CAplus.

(EtO)₂PONa from 0.9 g. Na and 5.35 g. (EtO)₂POH in Et₂O was treated with 10 g. Ph₂CHBr in Et₂O-C₆H₆; after 2 hrs. on the steam bath the filtered solution gave on evaporation 61.33% (CHPh₂)₂ and 5.3 g. yellow oil. No reaction took place when (EtO)₂PONa, prepared as above, was treated with Ph₂CHCl; the reaction also failed in hot (iso-Am)₂O. The reaction did proceed in refluxing MePh (2 hrs.), yielding (EtO)₂POH, Ph₂CHOH, (Ph₂CH)₂O, and a low yield of Ph₂CHP(O)(OEt)₂, b₄ 184-8°, d₀²⁰ 1.12775, n_D²⁰ 1.5450, m. 38-40°; hydrolyzed with 10% HCl 8 hrs. at 170-5° in a sealed tube, it gave the free acid, m. 223-5° (from H₂O). Addition of 8 g. (EtO)₃P in Et₂O to 12 g. Ph₂CHBr in Et₂O, followed by refluxing 1 hr. gave 43.6% yield of the same product, b₂ 180-1°, d₀²⁰ 1.1287, n_D²⁰ 1.5445, which slowly solidified and m. 39-40°; hydrolysis with 10% HCl at 150-80° gave the free acid, m. 227-8°. Addition of 13.8 g. PhCH₂Cl to (EtO)₂ONa from 15.6 g. ester in Et₂O, followed by 0.5 hr. reflux gave 49.35% PhCH₂P(O)(OEt)₂, b₁₁ 153-4°, d₀⁰ 1.1200, n_D²⁰ 1.4965; hydrolysis gave the free acid, m. 169-70° (from EtOH). Similar reaction with PhCH₂Br gave 44% yield of the same ester, b₁₂ 153-5°, d₀⁰ 1.1189, n_D²⁰ 1.4892, while PhCH₂I gave 21.1% yield of the same ester. To (EtO)₂PONa (from 15.85 g. ester) in Et₂O was added 14 g. (Me₂CBr)₂ resulting in a rapid reaction (7 min.); after filtration the mixture yielded 50% Me₂C:CMe₂.

Sbornik Statei po Obshchei Khimii published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Formula: C6H12Br2.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Olah, George A. published the artcileStable carbonium ions. XLVIII. Halonium ion formation via neighboring halogen participation. Tetramethylethylene halonium ions, Formula: C6H12Br2, the publication is Journal of the American Chemical Society (1967), 89(18), 4744-52, database is CAplus.

cf. preceding abstracts Bridged halonium ions (e.g. I) formed on ionization of 2,3-dihalo-2,3-dimethylbutanes in SbF5-SO2 solution at -60°, when the participating halogen atom is Cl, Br, or iodine. 2,3-Difluoro-2,3-dimethylbutane, on the other hand, gave α-fluoroisopropyl-dimethylcarbonium ion in which the F atom is rapidly exchanging intramolecularly between the two equivalent sites. 2-Halo-3-acetoxy-2,3-dimethylbutanes and 2-halo-3-methoxy-2,3-dimethylbutanes also ionize in SbF5-SO2 to similar ions. Bridged acetoxonium ion formation but not bridged methoxonium ion formation accompany these ionizations. 27 references.

Journal of the American Chemical Society published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Formula: C6H12Br2.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Balme, Genevieve published the artcileTotal synthesis of the triquinane marine sesquiterpene (±)-Δ⁹⁽¹²⁾-capnellene using a palladium-catalyzed bis-cyclization step, SDS of cas: 69361-41-7, the publication is Tetrahedron (1994), 50(2), 403-14, database is CAplus.

Details of a novel palladium catalyzed cyclization approach to linear condensed cyclopentanoids are reported. The mechanism of this reaction which involves a δ-ethylenic (or δ-acetylenic) carbon nucleophile and an unsaturated halide is a “Wacker type process” i.e., an attack by the nucleophile onto the unsaturation electrophilically activated by an organopalladium(II) species. In this paper, the authors will show the intramol. version of this reaction which then leads to the tricyclic framework of the sesquiterpene (±)-Δ⁹⁽¹²⁾-capnellene (I; R = Me), the total synthesis of which is described. Thus, cyclopentene II was prepared and underwent palladium-catalyzed cyclization to give triquinane I (R = CO₂Me) which gave I (R = Me) in 2 steps.

Tetrahedron published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, SDS of cas: 69361-41-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Kratzer, Domenic published the artcileSynthetic Route to Sulfobetaine Methacrylates with Varying Charge Distance, Safety of Sodium 3-bromopropane-1-sulfonate, the publication is European Journal of Organic Chemistry (2014), 2014(36), 8064-8071, database is CAplus.

A general synthetic strategy is described that enables access to a library of new sulfobetaine methacrylates starting from com. available precursors. The three-step procedure allows the distance between the quaternary amine and the sulfonate group (inner charge distance) to be varied by selecting the corresponding dibromoalkane in the first step. A key step is the final esterification, in which methacrylic acid acts as solvent as well as reagent for the zwitterionic hydroxy intermediates. Thus, it is possible to synthesize monomeric precursors with up to twelve methylene groups between the pos. and the neg. charge. A selection of these monomers has been successfully tested for their ability to polymerize using free-radical polymerization

European Journal of Organic Chemistry published new progress about 55788-44-8. 55788-44-8 belongs to bromides-buliding-blocks, auxiliary class Bromide,Salt,Aliphatic hydrocarbon chain,Aliphatic hydrocarbon chain, name is Sodium 3-bromopropane-1-sulfonate, and the molecular formula is C3H6BrNaO3S, Safety of Sodium 3-bromopropane-1-sulfonate.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Kuivila, Henry G. published the artcileElectrophilic displacement reactions. XIV. Two novel reactions involving areneboronic acids and halogens, Application of 2-Bromo-5-methoxybenzene boronic acid, the publication is Journal of Organic Chemistry (1962), 825-9, database is CAplus.

cf. CA 56, 15531f. Bromination of m-MeOC₆H₃B(OH)₂ (I) with 1, 2, and 3 moles Br yielded 2,5-Br(MeO)C₆H₃B(OH)₂ (II), 2,4,5-Br₂(MeO)C₆H₂B(OH)₂ (III), and 2,4,5-Br₃C₆H₂OMe (IV). Chlorination gave 2,5-Cl(MeO)- C₆H₃B(OH)₂ (V) and probably 4,3-Cl(MeO)C₆H₃B(OH)₂ (VI). Reaction with ICl gave 2,5-I(MeO)C₆H₃B(OH)₂ (VII). I anhydride (2.0 g.) in 75 ml. 1:4 AcOH-H₂O treated with stirring with 2 g. NaBr and 2.39 g. Br in 25 ml. 1:4 AcOH-H₂O and the mixture refrigerated 16 hrs. yielded 90% air-dried II, dried 1 hr. at 95° to give the anhydride, m. 213-15° (H₂O), partially reverting to II on standing several months. ZnCl₂ (2 g.) and 2.15 g. II heated in the pot of a liquid-liquid extractor and refluxed with steam distillation of the oily layer gave 92% p-BrC₆H₄OMe, n²⁵_D 1.5588; sulfonamide derivative m. 150.5-1.3°. I (2 g.) dibrominated in 100 ml. 1:4 AcOH-H₂O with 4 g. NaBr and 4.78 g. Br, the mixture refrigerated 2 days, and filtered yielded 92% III monohydrate. III monohydrate (2.0 g.) in 5 ml. MeOH kept 24 hrs. with 2.5 ml. 3.873M H₂O₂, the solvent evaporated on a steam bath, the oily product extracted with petr. ether, and the residue on evaporation (2.07 g.) repeatedly recrystallized from petr. ether (Norit) yielded 19% pure 2,4,5-Br₂(MeO)C₆H₂OH, m. 68-9°. I anhydride (1 g.) and 2.5 g. NaOAc in 60 ml. 1:2 MeOH-H₂O shaken 5 min. with 3.58 g. Br, the mixture kept 5 days, the solution evaporated, and extracted with 10% NaOH gave 57% solid, recrystallized from alc. to give 0.80 g. 2,4,5-Br₃C₆H₂OMe, m. 105-6°. I (2.0 g.) in a min. of hot H₂O₂ treated with 1.41 g. AcNHCl and 5 ml. concentrated HCl and the mixture cooled to room temperature yielded 43% Cl(MeO)C₆H₃B(OH)₂, m. 115° (solidifying and m. 190-5°), recrystallized to give V anhydride, m. to 220-3°. Further cooling yielded 43% isomeric VI, m. 146-51°. Treatment of V anhydride (0.3 g.) with 3 ml. Et₂O containing 0.047 g. C₅H₅N gave a C₅H₅N complex, m. 172-5°. Similarly, 0.3 g. VI and 0.053 g. C₅H₅N in Et₂O gave a complex, m. 156-9°. V (or VI) anhydride (2 g.) and 2 g. ZnCl₂ in 15 ml. H₂O refluxed 19 hrs. in a liquid-liquid extractor and the distilled ClC₆H₄OMe dried over KOH gave infrared spectra identical with those of o- and p-ClC₆H₄OMe, resp. V-VI (1 g.) treated with 2 g. (HOCH₂CH₂)₂NH and the complex, ν 3140 cm.^-1, hydrolyzed with dilute HCl and aqueous ZnCl₂ gave only p-ClC₆H₄OMe. I anhydride (2 g.) in 70 ml. CCl₄ heated 15 min. on a steam bath with 2.8 g. ICl in 20 ml. CCl₄, the refrigerated mixture filtered, the filtrate titrated with thiosulfate to show the use of 25% of ICl in chlorination and 50% in iodination, and the precipitate recrystallized repeatedly from CCl₄ gave 0.77 g. VII anhydride, m. 84-7°, neutralization equivalent 260 (with conversion to p-IC₆H₄OMe, m. 51-3°). The anhydride reverted readily to VII. The initial filtrate yielded 0.38 g. crude Cl(MeO)C₆H₃B(OH)₂ anhydrides. H₂O (50 ml. containing 4.0 g. NaOH and 10 millimoles Br treated with 10 millimoles PhB(OH)₂ with consumption in 15 min. of 4.9 millimoles Br for substitution and 5.1 millimoles in oxidation, the mixture acidified, and filtered yielded 20% 2,4,6-Br₃C₆H₂OH (VIII), m. 79.5-82.5°. NaOBr (19.5 millimoles) in 50 ml. H₂O kept 1 hr. with 4.88 millimoles PhB(OH)₂ in 20 ml. H₂O, acidified with HNO₂, filtered, and the air-dried precipitate (1.3 g.) treated with 5 ml. alc. gave 0.8 g. insoluble unidentified compound, m. gradually above 180°. Dilution of the filtrate with H₂O yielded 28% VIII. Br (15 millimoles) and 28 millimoles NaOH in 10 ml. H₂O kept 1 hr. with 5 millimoles p-BrC₆H₄B(OH)₂ and the product acidified yielded 78% VIII. PhB(OH)₂ (9.63 millimoles) in 5 ml. H₂O treated with 40.45 millimoles NaOCl in 75 ml. H₂O, the solution heated 1 hr. at 80°, the cooled solution treated with 1 g. NaHSO₃, acidified, filtered, and the product steam distilled yielded 90% 2,4,6-Cl₃C₆H₂OH, m. 67.5-8.0; p-nitrobenzoate m. 103.5-5.0°. Repetition with equimolar amounts of NaOCl and PhB(OH)₂ and distillation yielded 80% PhOH, b. 182-7°; p-nitrobenzoate corresponding to that of PhOH. NaOCl (10 millimoles) and 10 millimoles PhB(OH)₂ in 25 ml. H₂O heated 30 min. at 80° and the product analyzed for Cl showed that 8.11 millimoles NaOCl had been used for oxidation but only 1.89 millimoles for nuclear chlorination.

Journal of Organic Chemistry published new progress about 89694-44-0. 89694-44-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronic Acids,Boronic acid and ester, name is 2-Bromo-5-methoxybenzene boronic acid, and the molecular formula is C7H8BBrO3, Application of 2-Bromo-5-methoxybenzene boronic acid.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Adam, Julia M. published the artcileCyclodextrin-Derived Host Molecules as Reversal Agents for the Neuromuscular Blocker Rocuronium Bromide: Synthesis and Structure-Activity Relationships, SDS of cas: 55788-44-8, the publication is Journal of Medicinal Chemistry (2002), 45(9), 1806-1816, database is CAplus and MEDLINE.

A series of mono- and per-6-substituted cyclodextrin derivatives were synthesized as synthetic receptors (or host mols.) of rocuronium bromide, the most widely used neuromuscular blocker in anesthesia. By forming host-guest complexes with rocuronium, these cyclodextrin derivatives reverse the muscle relaxation induced by rocuronium in vitro and in vivo and therefore can be used as reversal agents of the neuromuscular blocker to assist rapid recovery of patients after surgery. Because this supramol. mechanism of action does not involve direct interaction with the cholinergic system, the reversal by these compounds is not accompanied by cardiovascular side effects usually attendant with acetylcholinesterase inhibitors such as neostigmine. The structure-activity relationships are consistent with this supramol. mechanism of action and are discussed herein. These include the effects of binding cavity size and hydrophobic and electrostatic interaction on the reversal activities of these compounds

Journal of Medicinal Chemistry published new progress about 55788-44-8. 55788-44-8 belongs to bromides-buliding-blocks, auxiliary class Bromide,Salt,Aliphatic hydrocarbon chain,Aliphatic hydrocarbon chain, name is Sodium 3-bromopropane-1-sulfonate, and the molecular formula is C3H6BrNaO3S, SDS of cas: 55788-44-8.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary