Tag: M.W=150-200

Lv, Xunlei published the artcileAssignment of NMR data and Conformational analysis of larotrectinib and its precursors, Related Products of pyrazoles-derivatives, the publication is Tetrahedron (2021), 132064, database is CAplus.

NMR experiments were used to identify the two main conformations of Larotrectinib and its synthetic precursor, the nitro compound 4. Conformational anal. by dynamic NMR was performed in different temperature and solvents, combining 2D EXSY and NOE experiments The results revealed the conformations of Larotrectinib and compound 4 were caused by the barrier to rotation of C11-N17. Meanwhile, the conformational specific structures of compound 4 were postulated based on NOE data and mol. simulation. The complete assignments of ¹H and ¹³C NMR data for compounds 1, 4 and 5 were reported for the first time.

Tetrahedron published new progress about 1363380-51-1. 1363380-51-1 belongs to pyrazoles-derivatives, auxiliary class Other Aromatic Heterocyclic,Chloride,Nitro Compound, name is 5-Chloro-3-nitropyrazolo[1,5-a]pyrimidine, and the molecular formula is C6H3ClN4O2, Related Products of pyrazoles-derivatives.

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

Li, Weipeng published the artcileCooperative Au/Ag Dual-Catalyzed Cross-Dehydrogenative Biaryl Coupling: Reaction Development and Mechanistic Insight, Category: pyrazoles-derivatives, the publication is Journal of the American Chemical Society (2019), 141(7), 3187-3197, database is CAplus and MEDLINE.

In the presence of (Me₂S)AuCl and AgOAc, pyrazoles such as 1-phenylpyrazole underwent chemoselective and regioselective oxidative dehydrogenative coupling reactions with fluorinated arenes and pyridines such as 2,3,5,6-tetrafluoropyridine mediated by PhI(OAc)₂ in 1,4-dioxane to yield (fluoroaryl)pyrazoles such as I. The mechanism of the oxidative coupling reaction was studied by determination of the reaction kinetics, kinetic isotope effects, and deuterium exchange, by generation and preparation of gold and silver complexes as potential intermediates, and by DFT calculations of transition state structures and energies for arene metalation, transmetalation, and reductive elimination reactions. Silver acetate is determined to be is the actual catalyst for C-H activation of electron-poor arenes, rather than gold(I) complexes. A mechanism of gold/silver dual catalysis is proposed, in which silver is responsible for the activation of electron-poor fluoroarenes via a concerted metalation-deprotonation pathway, and gold is responsible for the activation of electron-rich pyrazoles via an electrophilic aromatic substitution process. Kinetic studies reveal that C-H activation of pyrazoles by fluoroarylgold complexes is most likely the rate-limiting step.

Journal of the American Chemical Society published new progress about 1268520-92-8. 1268520-92-8 belongs to pyrazoles-derivatives, auxiliary class Other Aromatic Heterocyclic,Chloride, name is 4-Chloro-1-methyl-1H-pyrazolo[3,4-b]pyridine, and the molecular formula is C7H6ClN3, Category: pyrazoles-derivatives.

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

Bookser, Brett C. published the artcileSolvent-Controlled, Site-Selective N-Alkylation Reactions of Azolo-Fused Ring Heterocycles at N1-, N2-, and N3-Positions, Including Pyrazolo[3,4-d]pyrimidines, Purines, [1,2,3]Triazolo[4,5]pyridines, and Related Deaza-Compounds, Application In Synthesis of 1268520-92-8, the publication is Journal of Organic Chemistry (2018), 83(12), 6334-6353, database is CAplus and MEDLINE.

Alkylation of 4-methoxy-1H-pyrazolo[3,4-d]pyrimidine (1b) with iodomethane in THF using NaHMDS as base selectively provided N2-Me product 4-methoxy-2-methyl-2H-pyrazolo[3,4-d]pyrimidine (3b) in an 8/1 ratio over N1-Me product (2b). Interestingly, conducting the reaction in DMSO reversed selectivity to provide a 4/1 ratio of N1/N2 methylated products. Crystal structures of product 3b with N1 and N7 coordinated to sodium indicated a potential role for the latter reinforcing the N2-selectivity. Limits of selectivity were tested with 26 heterocycles which revealed that N7 was a controlling element directing alkylations to favor N2 for pyrazolo- and N3 for imidazo- and triazolo-fused ring heterocycles when conducted in THF. Use of ¹H-detected pulsed field gradient-stimulated echo (PFG-STE) NMR defined the mol. weights of ionic reactive complexes. This data and DFT charge distribution calculations suggest close ion pairs (CIPs) or tight ion pairs (TIPs) control alkylation selectivity in THF and solvent-separated ion pairs (SIPs) are the reactive species in DMSO.

Journal of Organic Chemistry published new progress about 1268520-92-8. 1268520-92-8 belongs to pyrazoles-derivatives, auxiliary class Other Aromatic Heterocyclic,Chloride, name is 4-Chloro-1-methyl-1H-pyrazolo[3,4-b]pyridine, and the molecular formula is C7H6ClN3, Application In Synthesis of 1268520-92-8.

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

Beyer, Hans published the artcileThiazoles. XXIX. The condensation products of thiosemicarbazide with ethyl α-chloroacetoacetate and a novel ring contraction of 2-amino-5-methyl-6-carbethoxy-1,3,4-thiadiazine to 3-methyl-4-carbethoxy-5-aminopyrazole, Synthetic Route of 23286-70-6, the publication is Chemische Berichte (1956), 1652-8, database is CAplus.

On condensation of AcCHClCO₂Et (I) with H₂NNHCSNH₂ (II), 4-methyl-5-carbethoxy-2-thiazolylhydrazine (III), MeC(:NNHCSNH₂)CHClCO₂Et (IV), or 3-amino-4-methyl-5-carbethoxy-2-thiazolone imide (V) is formed, depending upon the pH and temperature Refluxing 13.3 g. 1-acetylthiosemicarbazide and 8.5 g. NaOAc in 75 cc. absolute EtOH in a CO₂ atm., adding dropwise within 15 min. 16.5 g. I in 25 cc. absolute EtOH, and refluxing the mixture another hr. yield 96% N’-acetyl-N-(4-methyl-5-carbethoxy-2-thiazolyl)hydrazine (VI), fine needles, m. 227°, which (12.2 g.), refluxed in 75 cc. absolute EtOH 1 hr. with 5.3 cc. concentrated HCl, gives 88% III.HCl, needles, m. 189-90°. III.HCl is also formed in 80% yield when 4.1 g. I in 3 cc. EtOH is added (15 min.) to 2.28 g. II in 20 cc. EtOH at 50° (free III, liberated with NaOAc, 100%, leaflets, m. 186°; di-Ac derivative, prepared by heating 2.01 g. III or 2.43 g. VI with 15 cc. Ac₂O 20 min. on a water bath, 84%, needles, m. 198°; tri-Ac derivative, prepared by heating 2.01 g. III 15 min. in 10 cc. Ac₂O containing 5 drops concentrated H₂SO₄, prisms, m. 131°; monoformyl derivative, prepared by refluxing 2.01 g. III 1 hr. with 10 cc. 98% HCO₂H, 92%, fine needles, m. 205°). Boiling 2.01 g. III 15 min. in 25 cc. Me₂CO yields 92% acetone (4-methyl-5-carbethoxy-2-thiazolyl)hydrazone, silky needles, m. 143°; PhCOMe derivative, 95%, m. 118°. Adding dropwise (1 hr.) 16.4 g. I to 9.1 g. II in 50 cc. 2N HCl at 0° yields 100% IV, also formed in 78% yield by mixing the 2 reagents in alc. solution without HCl; IV decompose on storage. Adding at 70° 9.5 g. IV to 60 cc. PrOH and bringing the mixture quickly to the boil give 74% 2-amino-5-methyl-6-carbethoxy-1,3,4-thiadiazine-HCl, decompose about 90° [free base (VII), liberated with saturated NaOAc solution, fine yellow needles, decompose above 80°; after 2-3 days it decompose with the formation of 3-methyl-4-carbethoxy-5-aminopyrazole (VIII)]. Heating VII or IV with the calculated amount of p-O₂NC₆H₄CHO (IX) in EtOH yields 40% IX (4-methyl-5-carbethoxy-2-thiazolyl)hydrazone, yellow needles, m. 244°; BzH analog, pale yellow leaflets, m. 189°, is prepared by treating III.HCl in 2N HCl with BzH and NaOAc, or in 93% yield by condensation of equimolar amounts of III and BzH. Heating 7.2 g. VII.HCl in 50 cc. concentrated HCl 15-20 min. on a water bath and concentrating the filtered solution to 1/3 its volume yield 66% V.HCl, fine needles, m. 242-4° (decomposition), which is also formed in 43% yield when 8.2 g. I is added to 4.6 g. II in 30 cc. hot concentrated HCl and the solution concentrated to 0.5 its volume (free V, needles, m. 130°; di-Ac derivative, prisms, m. 107-8°). Adding 1.28 g. NaNO₂ in H₂O to 2.4 g. V.HCl in 25 cc. 2N HCl at 0° and pouring the ice-cooled solution into 1.2 g. PhNMe₂ in dilute HCl give 2-(p-dimethylaminophenylazo)-4-methyl-5-carbethoxythiazole (X).HCl, deep blue crystals, from which NH₄OH liberates the free X, red-brown leaflets, m. 205°; X is also obtained in 43% yield when 3.7 g. 2-amino-4-methyl-5-carbethoxythiazole is diazotized at 0° and the diazonium solution is treated with 2.4 g. PhNMe₂. Refluxing 9.5 g. VII.HCl 1 hr. in 50 cc. 2N alc. HCl and filtering off the S formed yield 80% VIII.HCl, m. 187-9° [free base, leaflets containing 1 mole H₂O, m. 69°, m. 113° (H₂O-free); nitrate, prisms, m. 197-8° (decomposition); mono-Ac derivative, prisms, m. 91°]. Treating 4.1 g. VIII.HCl in 15 cc. H₂O and 3 cc. concentrated HCl at 0° with 1.38 g. NaNO₂ in 7 cc. H₂O, pouring the diazonium solution into ice cold 30% H₃PO₂, keeping the mixture overnight at 0°, and adding saturated NaOAc solution give 3-methyl-4-carbethoxypyrazole-H₂O, m. 46° (HCl salt, needles, sinters 145°, m. 160°). Diazotizing 2.5 g. VIII.HCl, adding the diazonium solution to 1.2 g. PhNMe₂ in dilute HCl, and then adding NaOAc give 70% 3-methyl-4-carbethoxy-5-(p-dimethylaminophenylazo)pyrazole, stout orange prisms, m. 172°.

Chemische Berichte published new progress about 23286-70-6. 23286-70-6 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Amine,Ester, name is Ethyl 5-amino-3-methyl-1H-pyrazole-4-carboxylate, and the molecular formula is C7H11N3O2, Synthetic Route of 23286-70-6.

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

Bouaik, Hassan published the artcileOptimal parameters and structural composition of bio-oil and biochar from intermediate pyrolysis of red algal biomass, Related Products of pyrazoles-derivatives, the publication is Comptes Rendus Chimie (2021), 24(Spec.Iss.1), 1-15, database is CAplus.

Intermediate pyrolysis of red algal biomass was performed in a fixed-bed tubular reactor. To study the parametric effect on product distribution, the experiments were carried out at different temperatures ranging from 400 to 600 °C and different heating rates of 15, 30 and 50 °C/min. The objective of this study is to understand the effect of pyrolysis temperature and heating rate on the yields and compositions of the pyrolysis products of red algal biomass. The bio-oil, biochar and biogas yields ranged between 33 and 45 wt%, 29 and 42 wt%, and 18 and 35 wt%, resp., at different pyrolysis conditions. The highest bio-oil yield (45.02%) was obtained at 450 °C temperature at a heating rate of 50 °C/min. The bio-oil was characterized by proximate and ultimate anal., FTIR, 1H-NMR and GC-MS anal. whereas the biochar was characterized by proximate, ultimate, FTIR, SEM and BET. Higher heating value and d. of the bio-oil were 20.11 MJ/kg, 1289 kg/m³, resp. The bio-oil with relatively high fuel potential can be obtained from the pyrolysis of the red algal biomass. The characterization of bio-oil showed a high percentage of aliphatic functional groups and presence of phenolic, ketone- and nitrogen-containing groups. The characterization results showed that the bio-oil obtained from red algal biomass can be potentially valuable as a source of value-added chems. The biochar obtained with a high heating value of 22.89 MJ/kg can be used as an adsorbent as well as a solid fuel.

Comptes Rendus Chimie published new progress about 890590-91-7. 890590-91-7 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Carboxylic acid, name is 3-Isopropyl-1H-pyrazole-5-carboxylic acid, and the molecular formula is C7H10N2O2, Related Products of pyrazoles-derivatives.

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

Lu, Xiaoyun published the artcileDiscovery of new chemical entities as potential leads against Mycobacterium tuberculosis, Product Details of C7H11N3O2, the publication is Bioorganic & Medicinal Chemistry Letters (2016), 26(24), 5916-5919, database is CAplus and MEDLINE.

A series of biheterocyclic (1H-indole, benzofuran, pyrazolo[1,5-a]pyrimidine, pyrazolo[1,5-a]pyrimidin-5(4H)-one, imidazo[2,1-b]thiazole, and pyrazolo[5,1-b]thiazole) derivatives were synthesized and evaluated for their anti-tubercular activities. The imidazo[2,1-b]thiazoles and pyrazolo[5,1-b]thiazoles exhibited promising anti-tubercular activity in varying degrees. Especially, the 2,6-dimethylpyrazolo[5,1-b]thiazole exhibited strong suppressing function against H37Ra strain with MIC value of 0.03 μg/mL. This compound also displayed good pharmacokinetic profiles with oral bioavailability (F) of 41.7% and a half-life of 13.4 h. Furthermore, this compound significantly reduced the bacterial burden in an autoluminescent H37Ra infected mouse model, suggesting its promising potential for development of anti-tubercular drugs.

Bioorganic & Medicinal Chemistry Letters published new progress about 23286-70-6. 23286-70-6 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Amine,Ester, name is Ethyl 5-amino-3-methyl-1H-pyrazole-4-carboxylate, and the molecular formula is C7H11N3O2, Product Details of C7H11N3O2.

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

Afolabi, Fatai published the artcileSynthesis of novel heteroleptic delocalised cationic pyrazole gold complexes as potent HepG2 cytotoxic agents, Safety of 4-Bromo-1-methyl-1H-pyrazol-5-amine, the publication is Dalton Transactions (2018), 47(43), 15338-15343, database is CAplus and MEDLINE.

A new series of cationic gold(I) pyrazole complexes were prepared in excellent yields as their perchlorate salts. Results of cell viability assays show that these novel complexes have good cytotoxic properties against the human HepG2 cancer cell line. These complexes showed promising anti-cancer activities and to our knowledge, pyrazoles have never been tested against this cell line. The regioselectivity of the complexation is also discussed in regards to the substitution pattern of the pyrazoles.

Dalton Transactions published new progress about 105675-85-2. 105675-85-2 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Bromide,Amine, name is 4-Bromo-1-methyl-1H-pyrazol-5-amine, and the molecular formula is C4H6BrN3, Safety of 4-Bromo-1-methyl-1H-pyrazol-5-amine.

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

Kudo, Noriaki published the artcileA versatile method for Suzuki cross-coupling reactions of nitrogen heterocycles, Application of (1-Isobutyl-1H-pyrazol-5-yl)boronic acid, the publication is Angewandte Chemie, International Edition (2006), 45(8), 1282-1284, database is CAplus and MEDLINE.

A wide-ranging study of Suzuki reactions which use nitrogen-containing heterocycles was described. This method was highly versatile (a single procedure was used for all substrates, including boronate esters and trifluoroborates), compatible with a variety of unprotected functionalities (e.g., NH₂– and OH-substituted substrates), and efficient even with inactivated aryl chlorides.

Angewandte Chemie, International Edition published new progress about 847818-64-8. 847818-64-8 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Boronic acid and ester,Pyrazole,Boronic Acids,Boronic acid and ester, name is (1-Isobutyl-1H-pyrazol-5-yl)boronic acid, and the molecular formula is C7H13BN2O2, Application of (1-Isobutyl-1H-pyrazol-5-yl)boronic acid.

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

Bercean, Vasile-Nicolae published the artcileNew azo compounds derived from 1H-5-amino-4-ethoxycarbonyl-3-methyl-pyrazole and 3-mono- or 1,3-disubstituted pyrazol-5-ones, Synthetic Route of 23286-70-6, the publication is Revista de Chimie (Bucharest, Romania) (2010), 61(4), 364-367, database is CAplus.

Pyrazole-derived azo compounds were designed, and the synthesis of the target compounds was achieved by a coupling reaction of 3-amino-5-methyl-1H-pyrazole-4-carboxylic acid Et ester (I) with pyrazolone derivatives The products thus obtained were confirmed by MS, IR, UV-VIS, ¹H-NMR, and ¹³C-NMR, and existed in multiple tautomeric forms.

Revista de Chimie (Bucharest, Romania) published new progress about 23286-70-6. 23286-70-6 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Amine,Ester, name is Ethyl 5-amino-3-methyl-1H-pyrazole-4-carboxylate, and the molecular formula is C7H11N3O2, Synthetic Route of 23286-70-6.

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

Bercean, Vasile-Nicolae published the artcileAzo compounds derived from 1H-5-amino-4-ethoxycarbonyl-3-methyl-pyrazole and phenols or phenolic derivatives and possibilities of their cyclization to pyrazolo[5,1-c]benzo[1,2-e][1,2,4]triazines, Computed Properties of 23286-70-6, the publication is Revista de Chimie (Bucharest, Romania) (2011), 62(2), 154-157, database is CAplus.

The coupling reaction of 1H-4-ethoxycarbonyl-3-methylpyrazol-5-yldiazonium chloride with phenols and phenolic derivatives led to 1H-5-arylazo-4-ethoxycarbonyl-3-methylpyrazoles. Cyclization of one of the latter compounds, [1H-4-ethoxycarbonyl-5-(4,6-dimethoxy-2-hydroxyphenylazo)-3-methylpyrazole] gave the corresponding pyrazolo[5,1-c]benzo[1,2-e][1,2,4]triazine.

Revista de Chimie (Bucharest, Romania) published new progress about 23286-70-6. 23286-70-6 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Amine,Ester, name is Ethyl 5-amino-3-methyl-1H-pyrazole-4-carboxylate, and the molecular formula is C7H11N3O2, Computed Properties of 23286-70-6.

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