Day: January 5, 2023

One-Pot Synthesis of Enantiopure Spiro[3,4-dihydrobenzo[b][1,4]oxazine-2,3′-oxindole] via Regio- and Stereoselective Tandem Ring Opening/Cyclization of Spiroaziridine Oxindoles with Bromophenols was written by Hajra, Saumen;Hazra, Atanu;Abu Saleh, S. K.. And the article was included in Journal of Organic Chemistry in 2019.Application of 6602-33-1 This article mentions the following:

A highly efficient regio- and stereoselective spiroaziridine ring opening with 2-bromophenols and a subsequent tandem cyclization reaction was developed for the one-pot synthesis of enantiopure 3,4-dihydrospiro[benzo[b][1,4]oxazine-2,3′-oxindole] with excellent enantiopurity (ee up to >99%). It is further extended to asym. synthesis of NH-free 3,4-dihydrospiro[benzo[b][1,4]oxazine-2,3′-oxindole] retaining the optical activity. In the experiment, the researchers used many compounds, for example, 2,6-Dibromo-3-hydroxypyridine (cas: 6602-33-1Application of 6602-33-1).

2,6-Dibromo-3-hydroxypyridine (cas: 6602-33-1) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Application of 6602-33-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design and synthesis of ruthenium bipyridine catalyst: An approach towards low-cost hydroxylation of arenes and heteroarenes was written by Shome, Sanchari;Singh, Surya Prakash. And the article was included in Tetrahedron Letters in 2017.Reference of 4373-61-9 This article mentions the following:

Two new ruthenium bipyridine complexes were designed and synthesized for intermol. Csp²-H hydroxylation. An environmentally begin and inexpensive oxidant was employed as an oxygen source thereby enhancing its applicability and resulting in the remarkable increase of yield. In the catalytic process a ruthenium (IV) cationic complex is formed which enables the regioselective C-O bonds formation and also proves to be tolerant to a broad substrate scope. Activation of C-H bonds adjacent to removable and non-removable directing groups have been explored efficiently. In the experiment, the researchers used many compounds, for example, 2-(m-Tolyl)pyridine (cas: 4373-61-9Reference of 4373-61-9).

2-(m-Tolyl)pyridine (cas: 4373-61-9) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Reference of 4373-61-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Rearrangement of N,N-Di-tert-butoxycarbonylpyridin-4-amines and Formation of Polyfunctional Pyridines was written by Liu, Yahua;Ding, Qiang;Wu, Xu. And the article was included in Journal of Organic Chemistry in 2008.Reference of 209798-48-1 This article mentions the following:

N,N-Di-tert-butoxycarbonylpyridin-4-amines I (R¹ = R² = Cl; R¹ = Cl, Br, tert-Bu, R² = H) were found to be rearranged to tert-Bu 4-(tert-butoxycarbonylamino)nicotinates II by treatment with LDA in THF. In the experiment, the researchers used many compounds, for example, (2-Chloro-pyridin-3-yl)-carbamic acid tert-butyl ester (cas: 209798-48-1Reference of 209798-48-1).

(2-Chloro-pyridin-3-yl)-carbamic acid tert-butyl ester (cas: 209798-48-1) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Reference of 209798-48-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The synthesis of the new C-nucleoside 6-deazaformycin B was written by Korouli, Stella;Lougiakis, Nikolaos;Marakos, Panagiotis;Pouli, Nicole. And the article was included in Synlett in 2008.Safety of 4-Methoxy-2-methylpyridine This article mentions the following:

The synthesis of the 6-deaza analog of formycin B I is described, through the condensation of lithiated 4-methoxy-2-methyl-3-trifluoroacetamidopyridine with a suitably protected ribonolactone, dehydration of the resulting hemiacetal, reduction and subsequent ring closure followed by protecting group manipulation. In the experiment, the researchers used many compounds, for example, 4-Methoxy-2-methylpyridine (cas: 24103-75-1Safety of 4-Methoxy-2-methylpyridine).

4-Methoxy-2-methylpyridine (cas: 24103-75-1) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Safety of 4-Methoxy-2-methylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design, synthesis, and evaluation of pyrrolidine based CXCR4 antagonists with in vivo anti-tumor metastatic activity was written by Li, Zhanhui;Wang, Xu;Lin, Yu;Wang, Yujie;Wu, Shuwei;Xia, Kaijiang;Xu, Chen;Ma, Haikuo;Zheng, Jiyue;Luo, Lusong;Zhu, Fang;He, Sudan;Zhang, Xiaohu. And the article was included in European Journal of Medicinal Chemistry in 2020.Synthetic Route of C7H6N2 This article mentions the following:

The design, synthesis and evaluation of novel CXCR4 antagonists were based on a pyrrolidine scaffold e.g., 3-(1,3-dioxolan-2-yl)-1-(3-methylpyridin-2-yl)propan-1one. The structural exploration/optimization identified numerous potent CXCR4 antagonists, represented by (S)-2-methyl-4-(4-methylpiperazin-1-yl)-6-((2-(3methylpyridin-2-yl)pyrrolidin-1-yl)methyl)pyrimidine, which displayed potent binding affinity to CXCR4 receptor (IC₅₀ = 79 nM competitively displacing fluorescent 12G5 antibody) and inhibited CXCL12 induced cytosolic calcium flux (IC₅₀ = 0.25 nM). Moreover, in a transwell invasion assay, (S)-2-methyl-4-(4-methylpiperazin-1-yl)-6-((2-(3methylpyridin-2-yl)pyrrolidin-1-yl)methyl)pyrimidine significantly mitigated CXCL12/CXCR4 mediated cell migration. The (S)-2-Methyl-4-(4-methylpiperazin-1-yl)-6-((2-(3methylpyridin-2-yl)pyrrolidin-1-yl)methyl)pyrimidine exhibited good physicochem. properties (MW 367, logD7.4 1.12, pKa 8.2) and excellent in vitro safety profiles (e.g., hERG patch clamp IC₅₀ > 30μM and minimal CYP isoenzyme inhibition). Importantly, (S)-2-methyl-4-(4-methylpiperazin-1-yl)-6-((2-(3methylpyridin-2-yl)pyrrolidin-1-yl)methyl)pyrimidine displayed much improved metabolic stability in human and rat liver microsomes. Lastly, (S)-2-Methyl-4-(4-methylpiperazin-1-yl)-6-((2-(3methylpyridin-2-yl)pyrrolidin-1-yl)methyl)pyrimidine demonstrated marked efficacy in a cancer metastasis model in mice. These results strongly support (S)-2-methyl-4-(4-methylpiperazin-1-yl)-6-((2-(3methylpyridin-2-yl)pyrrolidin-1-yl)methyl)pyrimidine as a prototypical lead for the development of promising CXCR4 antagonists as clin. candidates. In the experiment, the researchers used many compounds, for example, 4-Methylpicolinonitrile (cas: 1620-76-4Synthetic Route of C7H6N2).

4-Methylpicolinonitrile (cas: 1620-76-4) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Synthetic Route of C7H6N2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridinecarboxylic acid derivatives. I. Syntheses of 4-substituted compounds of picolinic acid and 5-ethylpicolinic acid was written by Endo, Masaru;Nakashima, Tatsumi. And the article was included in Yakugaku Zasshi in 1960.HPLC of Formula: 24103-75-1 This article mentions the following:

2,4-Me(O₂N)C₅H₃N(O) in MeOH, EtOH, or PhCH₂OH with RONa gave 2,4-MeRC₅H₃N(O) (I) (R = MeO, EtO, PhO, and PhCH₂O). I in CHCl₃ at 0° treated with PCl₅, stirred 1 hr. at room temperature, heated 30 min. on a H₂O bath, the solvent removed in vacuo, the residue poured into ice H₂O, and the product extracted with CHCl₃ gave 2,4-MeRC₅H₃N (II) (R, % yield, b.p./mm. or m.p., and m.p. of picrate given): MeO, 59.9, 60°/5, 146-7°; EtO, 57.2, 86-9°/8, 135-6°; PhO, 67.9, 161°/1, 120-1°; PhCH₂O, 84.5, 88-92°, 168°. II in H₂O heated with KMnO₄, the solution concentrated, adjusted to pH 4-4.8, saturated CuSO₄ solution added, the precipitate filtered off, suspended in hot H₂O, H₂S gas passed in, the solution concentrated, and the residue recrystallized (EtOH) gave 4,2-R(HO₂C)C₅H₃N (III) (R, % yield, and m.p. given): MeO, 25.2, 196° EtO, 7, 153-5°; PhO, 32.2, 178-9°. A solution of RONa in ROH treated with 2,4,5-Me(O₂N)EtC₅H₂N(O), the mixture refluxed 2 hrs., the solvent removed, and the residue extracted with CHCl₃ gave 2,4,5-MeREtC₅H₂N(O) (IV) (R = MeO or EtO). Also, 100 ml. AcCl treated with 20 g. 2,4,5-Me(O₂N)EtC₅H₂N(O) portionwise, the mixture refluxed 10 min., the solution made alk. with Na₂CO₃, and the product extracted with CHCl₃ gave 19.5 g. IV (R = Cl). IV and Ac₂O heated at 100°, refluxed 15 min., and the product distilled gave 4,5,2-REt(AcOCH₂)C₅H₂N (V) (R, % yield, and b.p./mm. given): MeO, 62.7, 140°/6 (picrate m. 119-21°); EtO, 53.5, 150-4°/7 [picrolonate m. 184-6° (decomposition)]; Cl, 47.6, 133-5°/6 [picrolonate m. 138-41° (decomposition)]. V and 10% HCl heated 1 hr. on a H₂O bath, cooled, the solution made alk. with K₂CO₃, and the product extracted with CHCl₃, gave 4,5,2-REt(HOCH₂)C₅H₂N (VI) (R, % yield, b.p./mm. and m.p. of picrate given): MeO, 66.5, 140°/5, 73°; EtO, 59.3, 135-8°/4, 53-5°; Cl, 82.3, 132-4°/6, -. VI in CHCl₃ and activated MnO₂ stirred 2 hrs. and the CHCl₃ layer concentrated gave 4,5,2-REt(OHC)C₅H₂N (VII) (R, % yield, b.p./mm. and m.p. of semicarbazone given): MeO, 48.4, 99-101°/6, 190-3°; EtO, 58.8, 109-10°/6, 175-8°; Cl, 52.5, 83-8°/6, 227-8°. AgNO₃ (1.4 g.) in 14.1 ml. 20% NH₄OH and 1.4 g. NaOH in 14.1 ml. H₂O were mixed, stirred 1 hr. with 1 g. VII (R = MeO), kept overnight, the solution filtered, the filtrate acidified with HCl, evaporated to dryness, the residue taken up in EtOH, the EtOH removed, the residue in a small amount of H₂O adjusted to pH 2-3, Cu(OAc)₂ solution added, the precipitate decomposed with H₂S, the solution concentrated, and the residue recrystallized (EtOH) gave 0.2 g. 4,5,2-REt(HO₂C)C₅H₂N (VIII) (R = MeO), m. 150-2°. VII (R = EtO) (0.6 g.) in 8 ml. Me₂CO and 0.5 ml. 30% H₂O₂ kept 1.5 hrs., kept overnight with 0.7 ml. addnl. H₂O₂, the Me₂CO removed, the residue in 25 ml. H₂O refluxed 1 hr., and the product concentrated gave 0.2 g. VIII (R = EtO), m. 148-9° (C₆H₆). Similarly, 1.5 g. VII (R = Cl) yielded 0.8 g. VIII (R = Cl), m. 134-6°. In the experiment, the researchers used many compounds, for example, 4-Methoxy-2-methylpyridine (cas: 24103-75-1HPLC of Formula: 24103-75-1).

4-Methoxy-2-methylpyridine (cas: 24103-75-1) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals.HPLC of Formula: 24103-75-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Discovery and Development of 3-(6-Chloropyridine-3-yloxymethyl)-2-azabicyclo[3.1.0]hexane Hydrochloride (SUVN-911): A Novel, Potent, Selective, and Orally Active Neuronal Nicotinic Acetylcholine α4β2 Receptor Antagonist for the Treatment of Depression was written by Nirogi, Ramakrishna;Mohammed, Abdul Rasheed;Shinde, Anil K.;Ravella, Srinivasa Rao;Bogaraju, Narsimha;Subramanian, Ramkumar;Mekala, Venkat Reddy;Palacharla, Raghava Choudary;Muddana, Nageswararao;Thentu, Jagadeesh Babu;Bhyrapuneni, Gopinadh;Abraham, Renny;Jasti, Venkat. And the article was included in Journal of Medicinal Chemistry in 2020.Electric Literature of C5H5NO This article mentions the following:

A series of chem. optimizations guided by in vitro affinity at the α4β2 receptor in combination with selectivity against the α3β4 receptor, pharmacokinetic evaluation, and in vivo efficacy in a forced swim test resulted in identification of 3-(6-chloropyridine-3-yloxymethyl)-2-azabicyclo[3.1.0]hexane hydrochloride, I, (SUVN-911) as a clin. candidate. Compound I is a potent α4β2 receptor ligand with a K_i value of 1.5 nM. It showed >10μM binding affinity toward the ganglionic α3β4 receptor apart from showing selectivity over 70 other targets. It is orally bio-available and showed good brain penetration in rats. Marked antidepressant activity and dose-dependent receptor occupancy in rats support its potential therapeutic utility in the treatment of depression. It does not affect the locomotor activity at doses several folds higher than its efficacy dose. It is devoid of cardiovascular and gastrointestinal side effects. Successful long-term safety studies in animals and phase-1 evaluation in healthy humans for safety, tolerability, and pharmacokinetics paved the way for its further development. In the experiment, the researchers used many compounds, for example, Pyridin-4-ol (cas: 626-64-2Electric Literature of C5H5NO).

Pyridin-4-ol (cas: 626-64-2) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Electric Literature of C5H5NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

One-step synthesis of pyrimido[1,2-a][1,8]naphthyridinones, pyrido[1,2-a]pyrimidinones and 1,8-naphthyridinones. Antihypertensive agents. V was written by Ferrarini, Pier Luigi;Mori, Claudio;Primofiore, Giampaolo;Calzolari, Lorella. And the article was included in Journal of Heterocyclic Chemistry in 1990.Quality Control of N-(6-Aminopyridin-2-yl)acetamide This article mentions the following:

The cyclocondensation reaction of 2,6-diaminopyridine and 2-acetamido-6-aminopyridine with β-keto esters in polyphosphophoric acid to give 1,8-naphthyridinones, pyrido[1,2-a]pyrimidinones, and pyrimido[1,2-a][1,8]naphthyridinones was studied. Thus, cyclocondensation reaction of 2-acetamido-6-aminopyridine with ClCH₂COCH₂CO₂Et in polyphosphoric acid at 80° for 4 h gave 42% pyrimidonaphthyridinone I, the structure of which was confirmed by x-ray anal. In the experiment, the researchers used many compounds, for example, N-(6-Aminopyridin-2-yl)acetamide (cas: 1075-62-3Quality Control of N-(6-Aminopyridin-2-yl)acetamide).

N-(6-Aminopyridin-2-yl)acetamide (cas: 1075-62-3) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Quality Control of N-(6-Aminopyridin-2-yl)acetamide

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

O₂ Conversion to Esters by Fluoride-mediated Carboxylation of Organosilanes and Halide Derivatives was written by Frogneux, Xavier;von Wolff, Niklas;Thuery, Pierre;Lefevre, Guillaume;Cantat, Thibault. And the article was included in Chemistry – A European Journal in 2016.Recommanded Product: Methyl 3-methylpicolinate This article mentions the following:

A one-step conversion of carbon dioxide (CO₂) to heteroaromatic esters is presented under metal-free conditions. Using fluoride anions as promoters for the C-Si bond activation, pyridyl, furanyl, and thiophene organosilanes are successfully carboxylated with CO₂ in the presence of an electrophile. The mechanism of this unprecedented reaction has been elucidated based on exptl. and computational results, which show a unique catalytic influence of CO₂ in the C-Si bond activation of pyridylsilanes. The methodol. is applied to 18 different esters and it has enabled the incorporation of CO₂ to a polyester material for the first time. Under optimized conditions the synthesis of the target compounds was achieved using N,N,N-tributyl-1-butanaminium difluorotriphenylsilicate(1-) (i.e., tetrabutylammonium difluorotriphenylsilicate) as a reagent. Starting materials included carbon dioxide (CO₂), iodomethane (MeI) and silanes, such as 2-(trimethylsilyl)pyridine, 2-(trimethylsilyl)thiophene, 2-(trimethylsilyl)furan, 1-methyl-2-(trimethylsilyl)-2H-pyrrole, 2,6-bis(trimethylsilyl)pyridine. Reactants such as 3-(trimethylsilyl)pyridine did not provide products. A reaction of bis(trimethylsilyl)pyridine with iodomethane and carbon-dioxide provided a 2,6-pyridinedicarboxylic acid polyester polymer. In the experiment, the researchers used many compounds, for example, Methyl 3-methylpicolinate (cas: 59718-84-2Recommanded Product: Methyl 3-methylpicolinate).

Methyl 3-methylpicolinate (cas: 59718-84-2) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Recommanded Product: Methyl 3-methylpicolinate

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Supramolecular recognition: Protonmotive-driven switches or motors? was written by Crowley, James D.;Goshe, Andrew J.;Steele, Ian M.;Bosnich, Brice. And the article was included in Chemistry – A European Journal in 2004.COA of Formula: C6H6N2O3 This article mentions the following:

A dicationic mol. receptor bearing two cofacially disposed terpyridyl-Pd-Cl units forms stable 1:1 host-guest complexes with planar, neutral Pt(II) complexes. When the guest is modified to incorporate a pyridine group, the now basic guest is protonated by HO₂CCF₃ in MeCN solutions The basic yellow guest forms a stable, deep red 1:1 host-guest complex with the yellow Pd receptor. Addition of HO₂CCF₃ to this host-guest complex leads to the displacement of the guest from the receptor. Probably the dissociation of the guest is caused by electrostatic repulsion between the dicationic receptor and the pos. charged protonated guest. Addition of base restores the host-guest complex. This protonmotive translocation of the guest from the host to the solution is discussed in terms of the mechanisms that drive mol. motors, the power stroke and the Brownian ratchet. The system is best described as a mol. switch that operates by the same mechanism as one stroke of a mol. motor. The mol. structures of a dipalladium(II) host and of a platinum(II) ammine O-N-O Schiff base chelate were determined by x-ray crystallog. In the experiment, the researchers used many compounds, for example, 3-Hydroxy-6-methyl-2-nitropyridine (cas: 15128-90-2COA of Formula: C6H6N2O3).

3-Hydroxy-6-methyl-2-nitropyridine (cas: 15128-90-2) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.COA of Formula: C6H6N2O3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem