Month: December 2022

Robertson, Jeremy published the artcileSynthesis and Claisen rearrangement of bridged bicyclic enol ethers of relevance to the course of ketene s-cis-diene cycloaddition, Name: Diethyltrichloromethylphosphonate, the publication is Organic & Biomolecular Chemistry (2006), 4(23), 4307-4318, database is CAplus and MEDLINE.

The synthesis is described of a range of 3-alkylidene-2-oxabicyclo[2.2.1]hept-5-ene and 3-alkylidene-2-oxabicyclo[2.2.2]oct-5-ene derivatives; Claisen rearrangement of these substrates either thermally or in the presence of an added Lewis acid results in the formation of bicyclic cyclobutanones with generally good conversions. These reactions may be performed in hydroxylic solvents, supporting a largely non-dissociative pathway for the rearrangement.

Organic & Biomolecular Chemistry published new progress about 866-23-9. 866-23-9 belongs to chlorides-buliding-blocks, auxiliary class Aliphatic Chain, name is Diethyltrichloromethylphosphonate, and the molecular formula is C5H10Cl3O3P, Name: Diethyltrichloromethylphosphonate.

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

Kapp, Tobias G. published the artcileModification and functionalization of the guanidine group by tailor-made precursors, Application In Synthesis of 42074-68-0, the publication is Journal of Visualized Experiments (2017), e54873/1-e54873/7, database is CAplus and MEDLINE.

The guanidine group is one of the most important pharmacophoric groups in medicinal chem. The only amino acid carrying a guanidine group is arginine. In this article, an easy method for the modification of the guanidine group in peptidic ligands is provided, with an example of RGD-binding integrin ligands. It was recently demonstrated that the distinct modification of the guanidine group in these ligands allows for the selective modulation of the subtype (e.g., between the subtypes αv and α5). Moreover, a formerly unknown strategy for the functionalization via the guanidine group was demonstrated, and the synthetic approach is reviewed in this document. The modifications described here involve terminally (Nω) alkylated and acetylated guanidine groups. For the synthesis, tailor-made precursor mols. are synthesized, which are then subjected to a reaction with an orthogonally deprotected amine to transfer the pre-modified guanidine group. For the synthesis of alkylated guanidines, precursors based on N,N′-Di-Boc-1H-pyrazole-1-carboxamidine are used to synthesize acylated compounds, the precursor of choice being a correspondingly acylated derivative of N-Boc-S-methylisothiourea, which can be obtained in one- and two-step reactions.

Journal of Visualized Experiments published new progress about 42074-68-0. 42074-68-0 belongs to chlorides-buliding-blocks, auxiliary class Chloride,Benzyl chloride,Benzene, name is 2-Chlorotrityl chloride, and the molecular formula is C19H14Cl2, Application In Synthesis of 42074-68-0.

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

Cadogan, J. I. G. published the artcileReactivity of organophosphorus compounds. V. Reaction of trichloromethyl radicals with trialkyl phosphites, COA of Formula: C5H10Cl3O3P, the publication is Journal of the Chemical Society (1961), 3071-6, database is CAplus.

–From a knowledge of the reactions of benzyl and β,β-dimethylphenethyl radicals evidence was produced in favor of the radical-induced reaction of CCl₄ with trialkyl phosphites to give dialkyl trichloromethylphosphonates proceeding by a radical chain reaction involving [(RO)₃PCCl₃]⁺ Cl^– rather than by decomposition of the phosphoranyl radical (RO)₃(Cl₃C)P. Evidence concerning the reactivity of phosphoranyl radicals was presented and discussed. Benzyl di-Et phosphite (I) b₀.1 70°, n²_D⁵ 1.4900. PhCMe₂CH₂Cl (Ia), b₁2 101°, n²_D¹ 1.5241, was converted into the alc. as follows: O passed during 3 h. through a solution in Et₂O of the Grignard reagent from 250 g. Ia at 0°, and the mixture poured into 2 l. dilute H₂SO₄, washed, and distilled gave PhCMe₂CH₂OH (II), b₁2 110-12°, n²4_D 1.5248. II (25 g.) and 56.5 g. Et₃PO₃ kept 4.5 h. at 140°, the alc. formed removed, and the residue distilled gave 27 g. β,β-dimethylphenethyl di-Et phosphite (III), b_0.1 98-102°. Attempts to prepare tris(β,β-dimethylphenethyl) phosphite gave oils which readily decomposed when heated. I (5.3 g.) and 0.3 g. Bz₂O₂ in 15 mL. CCl₄ refluxed 18 h. gave 4 fractions: (a) 1.5 g. PhCH₂Cl, b. 40-80°, n²_D^3.5 1.5240; (b) 0.8 g., b. 80-90°, n²_D^3.5 1.5070; (c) 0.95 g., b. 90-110°, n²3.5_D 1.4770; and (d) 4.2 g. di-Et trichloromethylphosphonate (IV), b. 120-30°; n²_D³⁰⁵ 1.4620. Fractions (b) and (c) were mixtures of PhCH₂Cl and IV. Bz₂O₂ (0.44 g.) and 10 g. III in 24 g. CCl₄ refluxed 18 h. and evaporated gave a residue, shown by gas chromatog. to contain no Ia. A portion (50%) of the residue distilled gave an unsaturated oil, b₁₂ 90-105°, n²_D⁰ 1.5208, a 53:47 mixture of 2-methyl-1-phenylpropene and 2-methyl-3-phenylpropene. Distillation of a further portion, attempted at 10^-4 mm., gave an oil, b. 110°, n²_D⁴ 1.5080. Some decomposition occurred and the product was formulated as impure β,β-dimethylphenethyl Et trichloromethylphosphonate. Et₃PO₃ (5 g.) and 0.05 mol Bz₂O₂ in 15 g. CCl₄ refluxed 18 h. gave 6.85 g. IV. In a similar experiment, in which CCl₄ that had been passed through Al₂O₃ was used and the reaction carried out in the dark without Bz₂O₂, 6.94 g. IV was obtained. Ph₃PO₃ did not react with CCl₄ or BrCCl₃ under either of the above sets of conditions. The rate of disappearance of Et₃PO₃ on reaction with CCl₄ at 80° was determined by following the reaction by gas-liquid chromatog. The first-order rate constant was 2.2 × 10^-4 sec.^-1. The experiment was repeated in the presence of Bz₂O₂ to give a rate constant of 3.5 × 10^-4 sec.^-1 Et₃PO₃ (5 g.) and 15 mL. CCl₄ degassed and irradiated 1 h. at room temperature in a quartz flask with ultraviolet light gave 70% IV. Et₃PO₃ and CCl₄ did not react in the dark at room temperature in 7 h. tert-Bu₂O₂ (3.7 g.) in 18.4 g. PhMe and 31.1 g. CCl₄ was heated 48 h. at 130° in a sealed tube and the product separated into 2 fractions. Fraction (a) by gas-liquid chromatog. was shown to be largely PhCH₂Cl and fraction (b) of 1.2 g., was PhCH₂CH₂Ph with an unidentified component, possibly PhCH₂CCl₃. Bis(9-benzyl-9-fluorenyl) peroxide (0.5 g.), m. 170.0-0.5°, was heated 48 h. at 130° in a sealed tube with 2.2 mL. CCl₄ and 2 mL. C₆H₆; gas chromatog. showed the presence of (PhCH₂)₂ and PhCH₂Cl. Et₃PO₃ (8.3 g.), 15.4 g. CCl₄, 9 g. butane-1-thiol, and 0.61 g. Bz₂O₂ refluxed overnight, evaporated, and the 10.8-g. residue gas-chromatographed indicated tri-Et phosphorothionate, 18%; IV, 22%; and S-Bu di-Et phosphorothioate, 60%. Irradiation of 3.18 g. I in 15 mL. CCl₄ under N at room temperature 4 h. followed by fractionation, gave 0.70 g. PhCH₂Cl and 1.27 g. IV and left 1.8 g. of residue. Their nature was confirmed by IR spectra.

Journal of the Chemical Society published new progress about 866-23-9. 866-23-9 belongs to chlorides-buliding-blocks, auxiliary class Aliphatic Chain, name is Diethyltrichloromethylphosphonate, and the molecular formula is C5H10Cl3O3P, COA of Formula: C5H10Cl3O3P.

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

Jennings, Lee D. published the artcileDesign and synthesis of indolo[2,3-a]quinolizin-7-one inhibitors of the ZipA-FtsZ interaction, HPLC of Formula: 18791-02-1, the publication is Bioorganic & Medicinal Chemistry Letters (2004), 14(6), 1427-1431, database is CAplus and MEDLINE.

The binding of FtsZ to ZipA is a potential target for antibacterial therapy. Based on a small mol. inhibitor of the ZipA-FtsZ interaction, a parallel synthesis of small mols. was initiated which targeted a key region of ZipA involved in FtsZ binding. The X-ray crystal structure of one of these mols. complexed with ZipA was solved. The structure revealed an unexpected binding mode, facilitated by desolvation of a loosely bound surface water.

Bioorganic & Medicinal Chemistry Letters published new progress about 18791-02-1. 18791-02-1 belongs to chlorides-buliding-blocks, auxiliary class Aliphatic Chain, name is 2,3-Dibromopropionylchloride, and the molecular formula is C3H3Br2ClO, HPLC of Formula: 18791-02-1.

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

Brown, Louise M. published the artcileThe destruction of cytochrome P-450 by alclofenac: possible involvement of an epoxide metabolite, HPLC of Formula: 33697-81-3, the publication is Biochemical Pharmacology (1982), 31(2), 195-9, database is CAplus and MEDLINE.

In control mouse hepatic microsomes, no evidence for metabolism of alclofenac (I) [22131-79-9] was observed, but in induced (phenobarbitone or 3-methylcholanthrene) microsomes, I was metabolized to the dihydroxy [41451-01-8] and phenolic [33697-81-3] metabolites. Destruction of cytochrome P-450  [9035-51-2] was observed when I was incubated with microsomes from phenobarbitone-treated mice, but not untreated or 3-methylcholanthrene-treated mice; the destruction was dependent on the presence of a NADPH-regenerating system and was inhibited by SKF 525A, metyrapone, glutathione, and cysteine. The metabolites caused no loss of cytochrome P-450, whereas the reactive intermediate, alclofenac epoxide  [70319-10-7], was a potent inducer in the absence of NADPH. Thus, in vitro destruction of cytochrome P-450 by I is partly mediated through the formation of the reactive epoxy metabolite.

Biochemical Pharmacology published new progress about 33697-81-3. 33697-81-3 belongs to chlorides-buliding-blocks, auxiliary class Chloride,Carboxylic acid,Benzene,Phenol, name is 3-Chloro-4-hydroxyphenylacetic acid, and the molecular formula is C8H7ClO3, HPLC of Formula: 33697-81-3.

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

Taylor, Adam C. published the artcileUse of Chemcatcher passive sampler with high-resolution mass spectrometry and multi-variate analysis for targeted screening of emerging pesticides in water, HPLC of Formula: 67747-01-7, the publication is Analytical Methods (2020), 12(32), 4015-4027, database is CAplus and MEDLINE.

Pesticides present at trace concentrations are a common cause of poor water quality. Screening generates large qual. data sets, therefore, there is a need for improved monitoring methods and data interpretation strategies to reduce the need for repetition, and increase the quality of information for end-users. Passive sampling is an in situ time integrative technique, increasingly used for monitoring pesticides in water. Here, we describe a method using the Chemcatcher passive sampler, coupled to targeted screening using liquid chromatog.-quadrupole-time-of-flight mass spectrometry, and a com. available library. Statistical anal. was performed using Agilent Mass Profiler Professional software. Water sampling took place over one year, at three riverine sites in the south of England, UK. Statistical interpretation of time integrative data from passive sampling could distinguish regular and episodic pesticide inputs, and detected compounds neglected by routine monitoring methods. One hundred and eleven pesticides were identified including legacy and current use compounds with diverse origins and uses. Spatial and temporal trends were identified enabling prioritisation of seasonal monitoring at each site. This approach maximises the utility of qual. assessment and may help water quality managers to rationalise pesticide fate in future, providing significant addnl. insight without the need to increase the scope and cost of monitoring.

Analytical Methods published new progress about 67747-01-7. 67747-01-7 belongs to chlorides-buliding-blocks, auxiliary class Chloride,Amine,Benzene,Ether,Benzene Compounds, name is N-(2-(2,4,6-Trichlorophenoxy)ethyl)propan-1-amine, and the molecular formula is C15H25BN2O4, HPLC of Formula: 67747-01-7.

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

Tan, Derek S. published the artcileSynthesis and Preliminary Evaluation of a Library of Polycyclic Small Molecules for Use in Chemical Genetic Assays, Safety of 3-Carboxy-N,N,N-trimethylpropan-1-aminium chloride, the publication is Journal of the American Chemical Society (1999), 121(39), 9073-9087, database is CAplus.

(-)-Shikimic acid, was converted into both enantiomers of 2-hydroxyoxabicyclo[4.1.0]hept-3-ene-4-carboxylic acid which were attached to a solid support via a photocleavable linker. Tandem acylation-1,3-dipolar cycloaddition with nitrones yielded tetracyclic templates I. After development of several efficient coupling reactions of I and completion of extensive validation protocols, a split-pool synthesis yielded a binary encoded library calculated to contain 2.18 million polycyclic compounds These compounds are compatible with miniaturized cell-based forward chem. genetic assays designed to explore biol. pathways and reverse chem. genetic assays designed to explore protein function. As a simple illustration of the potential of these compounds, several were shown to activate a TGF-β-responsive reporter gene in mammalian cells.

Journal of the American Chemical Society published new progress about 6249-56-5. 6249-56-5 belongs to chlorides-buliding-blocks, auxiliary class Phase Transfer Catalyst,Inhibitor,Natural product, name is 3-Carboxy-N,N,N-trimethylpropan-1-aminium chloride, and the molecular formula is C12H15NO, Safety of 3-Carboxy-N,N,N-trimethylpropan-1-aminium chloride.

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

Zorn, Kimberley M. published the artcileMachine Learning Models for Estrogen Receptor Bioactivity and Endocrine Disruption Prediction, Computed Properties of 637-07-0, the publication is Environmental Science & Technology (2020), 54(19), 12202-12213, database is CAplus and MEDLINE.

The U. S. Environmental Protection Agency (EPA) periodically releases in vitro data across a variety of targets, including the estrogen receptor (ER). In 2015, the EPA used this data to construct math. models of ER agonist and antagonist pathways to prioritize chems. for endocrine disruption testing. However, math. models require in vitro data prior to predicting estrogenic activity, but machine learning methods are capable of prospective prediction from mol. structure alone. The current study describes the generation and evaluation of Bayesian machine learning models grouped by the EPA’s ER agonist pathway model, using multiple data types with proprietary software, Assay Central. External predictions with three test sets of in vitro and in vivo reference chems. with agonist activity classifications were compared to previous math. model publications. Training datasets were subjected to addnl. machine learning algorithms and compared with rank normalized scores of internal five-fold cross-validation statistics. External predictions were found to be comparable or superior to previous studies published by the EPA. When assessing six addnl. algorithms for the training datasets, Assay CentralTM performed similarly at a reduced computational cost. This study demonstrates machine learning can prioritize chems. for future in vitro and in vivo testing of ER agonism.

Environmental Science & Technology published new progress about 637-07-0. 637-07-0 belongs to chlorides-buliding-blocks, auxiliary class Inhibitor,Cell Cycle,PPAR, name is Ethyl 2-(4-chlorophenoxy)-2-methylpropanoate, and the molecular formula is C3H8N2S, Computed Properties of 637-07-0.

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

Feofanov, Mikhail published the artcileSolid-state construction of zigzag periphery via intramolecular C-H insertion induced by alumina-mediated C-F activation, Application of 4-Chloro-2-methylphenylboronic acid, the publication is Chemical Communications (Cambridge, United Kingdom) (2021), 57(92), 12325-12328, database is CAplus and MEDLINE.

Here, the alumina-mediated C-F bond activation (AmCFA) enabled construction of PAHs with zigzag periphery was reported. This method includes formal Csp³-H activation and opens an avenue for generation of carbon-based nanomagnets directly on technol. relevant surfaces.

Chemical Communications (Cambridge, United Kingdom) published new progress about 209919-30-2. 209919-30-2 belongs to chlorides-buliding-blocks, auxiliary class Chloride,Boronic acid and ester,Benzene,Boronic Acids,Boronic acid and ester, name is 4-Chloro-2-methylphenylboronic acid, and the molecular formula is C7H8BClO2, Application of 4-Chloro-2-methylphenylboronic acid.

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

Mistry, Nisha published the artcileCatalytic asymmetric synthesis of geminal-dicarboxylates, Related Products of chlorides-buliding-blocks, the publication is Chemical Science (2018), 9(29), 6307-6312, database is CAplus and MEDLINE.

Stereogenic acetals, spiroacetals and ketals are well-studied stereochem. features that bear two heteroatoms at a common carbon atom. These stereocenters are normally found in cyclic structures while linear (or acyclic) analogs bearing two heteroatoms are rare. Chiral geminal-dicarboxylates are illustrative, there is no current way to access this class of compounds while controlling the stereochem. at the carbon center bound to two oxygen atoms. Here, a rhodium-catalyzed asym. carboxylation of ester-containing allylic bromides to form stereogenic carbon centers bearing two different carboxylates with high yields and enantioselectivities is reported. The products, which are surprisingly stable to a variety of acidic and basic conditions, can be manipulated with no loss of enantiomeric purity as demonstrated by ring closing metathesis reactions to form chiral lactones, which have been extensively used as building blocks in asym. synthesis.

Chemical Science published new progress about 6313-54-8. 6313-54-8 belongs to chlorides-buliding-blocks, auxiliary class Pyridine,Chloride,Carboxylic acid, name is 2-Chloroisonicotinic acid, and the molecular formula is C6H4ClNO2, Related Products of chlorides-buliding-blocks.

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