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1. Sulfonylimination of Proline with Sulfonylazides Involving Aldehyde-Induced Decarboxylation Coupling

Author:
Liu, Hongyan; Pang, Zengfen; Hao, Liqiang; Sun, Jian; Zhang, Zheng; Wen, Fuqiang; Xia, Chengcai
Source:
Organic letters 2021 v.23 no.4 pp. 1234-1238
ISSN:
1523-7052
Subject:
proline,   etc   ; aldehydes; amidines; decarboxylation;     Show all 4 Subjects
Abstract:
... In the presence of aldehyde, a facile method was developed to obtain N-sulfonyl amidines under metal- and oxidant-free conditions by the decarboxylative of proline. This transformation features a double C–N bond formation and allows for the green synthesis of the N-sulfonyl amidines on the basis of mild conditions. ...
DOI:
10.1021/acs.orglett.0c04187

2. The family of sarcosine oxidases: Same reaction, different products

Author:
Lahham, Majd; Jha, Shalinee; Goj, Dominic; Macheroux, Peter; Wallner, Silvia
Source:
Archives of biochemistry and biophysics 2021 v.704 pp. 108868
ISSN:
0003-9861
Subject:
proline,   etc   ; biophysics; imines; oxidation; oxidoreductases; sarcosines;     Show all 6 Subjects
Abstract:
... The subfamily of sarcosine oxidase is a set of enzymes within the larger family of amine oxidases. It is ubiquitously distributed among different kingdoms of life. The member enzymes catalyze the oxidization of an N-methyl amine bond of amino acids to yield unstable imine species that undergo subsequent spontaneous non-enzymatic reactions, forming an array of different products. These products ran ...
DOI:
10.1016/j.abb.2021.108868

3. Ruthenium-Catalyzed Intramolecular Arene C(sp²)–H Amidation for Synthesis of 3,4-Dihydroquinolin-2(1H)-ones

Author:
Sun, Wenlong; Ling, Cho-Hon; Au, Chi-Ming; Yu, Wing-Yiu
Source:
Organic letters 2021 v.23 no.9 pp. 3310-3314
ISSN:
1523-7052
Subject:
proline,   etc   ; Lewis acids; p-cymene; regioselectivity;     Show all 4 Subjects
Abstract:
... We report the [Ru(p-cymene)(l-proline)Cl] ([Ru1])-catalyzed cyclization of 1,4,2-dioxazol-5-ones to form dihydroquinoline-2-ones in excellent yields with excellent regioselectivity via a formal intramolecular arene C(sp²)–H amidation. The reactions of the 2- and 4-substituted aryl dioxazolones proceeds initially through spirolactamization via electrophilic amidation at the arene site, which is par ...
DOI:
10.1021/acs.orglett.1c00781

4. Biocatalysts Based on Peptide and Peptide Conjugate Nanostructures

Author:
Hamley, Ian W.
Source:
Biomacromolecules 2021 v.22 no.5 pp. 1835-1855
ISSN:
1526-4602
Subject:
proline,   etc   ; biocatalysis; histidine; hydrolysis; micelles; nanotubes; peptides;     Show all 7 Subjects
Abstract:
... Peptides and their conjugates (to lipids, bulky N-terminals, or other groups) can self-assemble into nanostructures such as fibrils, nanotubes, coiled coil bundles, and micelles, and these can be used as platforms to present functional residues in order to catalyze a diversity of reactions. Peptide structures can be used to template catalytic sites inspired by those present in natural enzymes as w ...
DOI:
10.1021/acs.biomac.1c00240

5. Oligodimethylsiloxane-Oligoproline Block Co-Oligomers: the Interplay between Aggregation and Phase Segregation in Bulk and Solution

Author:
Lamers, Brigitte A.G.; Herdlitschka, Andreas; Schnitzer, Tobias; Mabesoone, Mathijs F.J.; Schoenmakers, Sandra M.C.; de Waal, Bas F.M.; Palmans, Anja R.A.; Wennemers, Helma; Meijer, E.W.
Source:
Journal of the American Chemical Society 2021 v.143 no.10 pp. 4032-4042
ISSN:
1520-5126
Subject:
proline,   etc   ; aggregation behavior; gels; siloxanes; solvents;     Show all 5 Subjects
Abstract:
... Discrete block co-oligomers (BCOs) assemble into highly ordered nanostructures, which adopt a variety of morphologies depending on their environment. Here, we present a series of discrete oligodimethylsiloxane-oligoproline (oDMS-oPro) BCOs with varying oligomer lengths and proline end-groups, and study the nanostructures formed in both bulk and solution. The conjugation of oligoprolines to apolar ...
DOI:
10.1021/jacs.1c01076

6. Biosynthesis of Nonimmunosuppressive ProlylFK506 Analogues with Neurite Outgrowth and Synaptogenic Activity

Author:
Jung, Jin A; Lee, Heon Joo; Song, Myoung Chong; Hwangbo, Areum; Beom, Ji Yoon; Lee, Soo Jung; Park, Dong Jin; Oh, Ji Hoon; Ha, Sang-Jun; Cheong, Eunji; Yoon, Yeo Joon
Source:
Journal of natural products 2021 v.84 no.2 pp. 195-203
ISSN:
1520-6025
Subject:
proline,   etc   ; biosynthesis; immunosuppression; moieties; neurites; synaptic transmission;     Show all 6 Subjects
Abstract:
... Separating the immunosuppressive activity of FK506 (1) from its neurotrophic activity is required to develop FK506 analogues as drugs for the treatment of neuronal diseases. Two new FK506 analogues, 9-deoxo-36,37-dihydro-prolylFK506 (2) and 9-deoxo-31-O-demethyl-36,37-dihydro-prolylFK506 (3) containing a proline moiety instead of the pipecolate ring at C-1 and modifications at the C-9/C-31 and C-3 ...
DOI:
10.1021/acs.jnatprod.0c00767

7. A metal-free method for the facile synthesis of indanones via the intramolecular hydroacylation of 2-vinylbenzaldehyde

Author:
He, Guoxue; Ma, Jinyu; Zhou, Jianhui; Li, Chunpu; Liu, Hong; Zhou, Yu
Source:
Green chemistry 2021 v.23 no.2 pp. 1036-1040
ISSN:
1463-9270
Subject:
proline,   etc   ; catalysts; drugs; green chemistry; indans;     Show all 5 Subjects
Abstract:
... A facile method for the synthesis of indanones was developed under metal- and additive-free conditions, wherein l-proline served as an efficient and environmentally benign catalyst. Compared with previously synthesized indanones, synthesis by the transition-metal-catalyzed intramolecular hydroacylation of 2-vinylbenzaldehyde provided a more green synthetic pathway to indanone scaffolds with good t ...
DOI:
10.1039/d0gc03572f

8. Visible-Light-Induced Tertiary C(sp³)–H Sulfonylation: An Approach to Tertiary Sulfones

Author:
Swarnkar, Sumedha; Ansari, Mohd Yeshab; Kumar, Atul
Source:
Organic letters 2021 v.23 no.4 pp. 1163-1168
ISSN:
1523-7052
Subject:
proline,   etc   ; drugs; iodine; photocatalysis; photocatalysts; sulfonylation;     Show all 6 Subjects
Abstract:
... In seeking to broaden the lexicon of photocatalysis and considering the importance of sulfones as essential pharmaceuticals, herein one-pot visible-light-induced tertiary C(sp³)–H sulfonylation is explored for the first time using indoline-2,3-diones, 4-hydroxy proline, and sulfinic acids as model substrates in the presence of iodine and Na₂-Eosin Y as a photocatalyst. In addition, this transforma ...
DOI:
10.1021/acs.orglett.0c03898

9. A DFT study on the C–H oxidation reactivity of Fe(iv)–oxo species with N4/N5 ligands derived from l-proline

Author:
Lin, Jin; Sun, Qiangsheng; Sun, Wei
Source:
RSC advances 2021 v.11 no.4 pp. 2293-2297
ISSN:
2046-2069
Subject:
proline,   etc   ; dissociation; hexane; hydrogen; hydroxylation; ligands; oxidation;     Show all 7 Subjects
Abstract:
... The hydroxylation of hexane by two FeᴵⱽO complexes bearing a pentadentate ligand (N5, Pro3Py) and a tetradentate ligand (N4, Pro2PyBn) derived from l-proline was studied by DFT calculations. Theoretical results predict that both FeᴵⱽO complexes hold triplet ground states. The hydrogen atom abstraction (HAA) processes by both FeᴵⱽO species proceed through a two-state reactivity, thus indicating tha ...
DOI:
10.1039/d0ra08496d

10. Surface-Only Spectroscopy for Diffusion-Limited Systems Using Ultra-Low-Temperature DNP MAS NMR at 16.4 T

Author:
Matsuki, Yoh; Sugishita, Tomoaki; Fujiwara, Toshimichi
Source:
Journal of physical chemistry 2020 v.124 no.34 pp. 18609-18614
ISSN:
1932-7455
Subject:
proline,   etc   ; temperature; tripeptides; urea;     Show all 4 Subjects
Abstract:
... The conventional dynamic nuclear polarization (DNP) technique at T ∼ 100 K can enhance sensitivity of magic-angle spinning (MAS) NMR over 100-fold for standard samples containing urea/proline under high-field conditions, B₀ = 9.4–16.4 T. In the scene of real applications, however, the achievable enhancement is often much lower than for urea/proline due to faster ¹H relaxation (T₁H) promoted by mol ...
DOI:
10.1021/acs.jpcc.0c04873

11. Synthesis of diverse 2,3,4,5-tetrahydro-1H-azepine derivatives via sequential Knoevenagel reaction and Michael addition of tertiary enamide

Author:
Yang, Hanlin; Ning, Zhipeng; Wang, Shiyu; Li, Jiazhu; Wang, Zu-Li; Wang, Wei-Li; Xu, Xin-Ming
Source:
Tetrahedron letters 2021 v.74 pp. 153174
ISSN:
0040-4039
Subject:
proline,   etc   ; catalytic activity; chemical reactions; heterocyclic nitrogen compounds;     Show all 4 Subjects
Abstract:
... An exquisite and practical access to construct seven-membered N-heterocyclic rings was established under mild conditions. Tertiary enamides underwent successively Knoevenagel reaction with different active methylene compounds and intramolecular Michael addition under the sequential catalysis of proline and AlCl₃ to afford diverse 2,3,4,5-tetrahydro-1H-azepine derivatives in high yields. The result ...
DOI:
10.1016/j.tetlet.2021.153174

12. Small extracellular ring domain is necessary for CD82/KAI1′anti-metastasis function

Author:
Ma, Xiaoguang; He, Xin; Wang, Congcong; Huang, Xiaohua; Li, Ying; Ma, Keli
Source:
Biochemical and biophysical research communications 2021 v.557 pp. 110-116
ISSN:
0006-291X
Subject:
proline,   etc   ; bioactive properties; cell movement; metastasis; neoplasm cells; peptides; research;     Show all 7 Subjects
Abstract:
... The peptide mimicking small extracellular loop of CD82/KAI1 has been reported to inhibit tumor cell migration and metastasis. This provides an evidence that small extracellular loop domain should be important for the function of CD82/KAI1. In this paper, to investigate the structure basis for the function of EC1 mimic peptide, we systematically analyzed the effects of each amino acid residue in EC ...
DOI:
10.1016/j.bbrc.2021.04.001

13. Self-Assembled Thermoresponsive Molecular Brushes as Nanoreactors for Asymmetric Aldol Addition in Water

Author:
Kuepfert, Michael; Ahmed, Eman; Weck, Marcus
Source:
Macromolecules 2021 v.54 no.8 pp. 3845-3853
ISSN:
1520-5835
Subject:
proline,   etc   ; active sites; catalysts; catalytic activity; composite polymers; micelles; temperature;     Show all 7 Subjects
Abstract:
... The manipulation and tunability of self-assembled block copolymers through external stimuli present an attractive strategy to develop smart polymer-based nanoreactors as supports for non-orthogonal tandem catalysis. We report on thermoresponsive core–shell micelles based on poly[norbornene-poly(2-methyl-2-oxazoline-block-2-propyl-2-oxazoline)]-graft-poly[norbornene l-proline] (P[NB-P(MeOx-b-PropOx ...
DOI:
10.1021/acs.macromol.0c02708

14. Recapitulating the Binding Affinity of Nrf2 for KEAP1 in a Cyclic Heptapeptide, Guided by NMR, X-ray Crystallography, and Machine Learning

Author:
Ortet, Paula C.; Muellers, Samantha N.; Viarengo-Baker, Lauren A.; Streu, Kristina; Szymczyna, Blair R.; Beeler, Aaron B.; Allen, Karen N.; Whitty, Adrian
Source:
Journal of the American Chemical Society 2021 v.143 no.10 pp. 3779-3793
ISSN:
1520-5126
Subject:
proline,   etc   ; X-radiation; X-ray diffraction; geometry; hydrophobicity; ligands; peptides;     Show all 7 Subjects
Abstract:
... Macrocycles, including macrocyclic peptides, have shown promise for targeting challenging protein–protein interactions (PPIs). One PPI of high interest is between Kelch-like ECH-Associated Protein-1 (KEAP1) and Nuclear Factor (Erythroid-derived 2)-like 2 (Nrf2). Guided by X-ray crystallography, NMR, modeling, and machine learning, we show that the full 20 nM binding affinity of Nrf2 for KEAP1 can ...
DOI:
10.1021/jacs.0c09799

15. One-pot four-component synthesis of methyl 4-(4-chlorophenyl)-5,7-dioxo-1-phenyl-1,4,5,6,7,8-hexahydropyrazolo [4′,3′:5,6] pyrano [2,3-d] pyrimidine-3-carboxylate; a green approach

Author:
Yadav, Maruti B.; Lim, Kwon Taek; Kim, Jong Su; Jeong, Yeon Tae
Source:
Tetrahedron letters 2021 v.65 pp. 152754
ISSN:
0040-4039
Subject:
proline,   etc   ; catalysts; methodology; protocols; solvents; synthesis; toxicity; yields;     Show all 8 Subjects
Abstract:
... A simple and efficient synthetic protocol for the synthesis of methyl 4-(4-chlorophenyl)-5,7-dioxo-1-phenyl-1,4,5,6,7,8-hexahydropyrazolo [4′,3′:5,6] pyrano[2,3-d] pyrimidine-3-carboxylate derivatives via a one pot four-component reaction catalyzed by l-Proline has been successfully developed. This new protocol produces pyrano pyrimidine carboxylate derivatives in good to excellent yields, with op ...
DOI:
10.1016/j.tetlet.2020.152754

16. l- Proline as a Valuable Scaffold for the Synthesis of Novel Enantiopure Neonicotinoids Analogs

Author:
Bonilla-Landa, Israel; Cuapio-Muñoz, Ulises; Luna-Hernández, Axel; Reyes-Luna, Alfonso; Rodríguez-Hernández, Alfredo; Ibarra-Juarez, Arturo; Suarez-Mendez, Gabriel; Barrera-Méndez, Felipe; Caram-Salas, Nadia; Enríquez-Medrano, J. Francisco; Díaz de León, Ramón E.; Olivares-Romero, José Luis
Source:
Journal of agricultural and food chemistry 2021 v.69 no.5 pp. 1455-1465
ISSN:
1520-5118
Subject:
proline,   etc   ; Xyleborus; dinotefuran; enantiomers; food chemistry; insecticidal properties; lead; neurotoxicity;     Show all 8 Subjects
Abstract:
... In this research, six neonicotinoid analogs derived from l-proline were synthesized, characterized, and evaluated as insecticides against Xyleborus affinis. Most of the target compounds showed good to excellent insecticidal activity. To the best of our knowledge, this is the first report dealing with the use of enantiopure l-proline to get neonicotinoids. These results highlighted the compound 9 a ...
DOI:
10.1021/acs.jafc.0c05997

17. Isolation of a Bacillus cereus strain HBL‐AI and its application for production of Trans‐4‐hydroxy‐l‐proline

Author:
Wang, X.‐M.; Han, M.‐N.; Jiang, J.‐P.; Fu, S.‐Q.; Zhang, F.‐H.; Du, J.; Zhang, H.‐L.; Li, W.
Source:
Letters in applied microbiology 2021 v.72 no.1 pp. 53-59
ISSN:
0266-8254
Subject:
procollagen-proline dioxygenase; proline,   etc   ; Bacillus cereus; Escherichia coli; air; bacteria; biotransformation; carbon; energy; genome; glucose; industrial applications;     Show all 12 Subjects
Abstract:
... A new trans‐4‐hydroxy‐l‐proline (trans‐Hyp) producing Bacillus cereus HBL‐AI, was isolated from the air, which was screened just using l‐proline as carbon and energy sources. This strain exhibited 73·4% bioconversion rate from initial l‐proline (3 g l⁻¹) to trans‐Hyp. By sequencing the genome of this bacterium, 6244 coding sequences were obtained. Genome annotation analysis and functional expressi ...
DOI:
10.1111/lam.13388

18. Prolidase – A protein with many faces

Author:
Wilk, Piotr; Wątor, Elżbieta; Weiss, Manfred S.
Source:
Biochimie 2020
ISSN:
0300-9084
Subject:
proline; proline dipeptidase,   etc   ; biotechnology; carcinogenesis; dipeptides; human health; humans; hydroxyproline;     Show all 8 Subjects
Abstract:
... Prolidase is a metal-dependent peptidase specialized in the cleavage of dipeptides containing proline or hydroxyproline on their C-termini. Prolidase homologues are found in all kingdoms of life. The importance of prolidase in human health is underlined by a rare hereditary syndrome referred to as Prolidase Deficiency. A growing number of studies highlight the importance of prolidase in various ot ...
DOI:
10.1016/j.biochi.2020.09.017

19. The role of pH in corrosion inhibition of tin using the proline amino acid: theoretical and experimental investigations

Author:
EL Ibrahimi, Brahim; Bazzi, Lahcen; EL Issami, Souad
Source:
RSC advances 2020 v.10 no.50 pp. 29696-29704
ISSN:
2046-2069
Subject:
proline,   etc   ; corrosion; electrochemistry; pH; tin;     Show all 5 Subjects
Abstract:
... Herein, the effect of a mediums' pH on the interfacial interactions between proline (Pro) amino acid and tin metal was studied. In this work, acidic and near-neutral pH values were considered. DFT-based calculations and Monte Carlo simulations were carried out in the aqueous phase to understand the role of pH in Pro/tin interactions. To confirm this role in terms of inhibition efficiency, the CC a ...
DOI:
10.1039/d0ra04333h

20. Biochemical metabolism of young plants of Ucuúba (Virola surinamensis) in the presence of cadmium

Author:
Júnior, W. V. Andrade; Neto, C. F. Oliveira; Filho, B. G. Santos; Cruz, E. D.; Amarante, C. B.; Barbosa, A. V. C.; Nogueira, G. A. S.; Nascimento, V. R.; Sousa, D. J. P.; Teixeira, J. S. S.
Source:
BMC plant biology 2021 v.21 no.1 pp. 151
ISSN:
1471-2229
Subject:
proline,   etc   ; Virola surinamensis; ammonia; cadmium; carbon metabolism; experimental design; forests; nitrate reductase; nitrates; nitrogen; phytoremediation; sucrose;     Show all 12 Subjects
Abstract:
... Virola surinamensis is a forest species widely distributed in the estuaries of the Amazon. These ecosystems are susceptible to contamination by Cadmium (Cd), indicating that the plant has strategies for tolerating this metal. The aim of this study was to assess the nitrogen and carbon metabolism of young plants of Ucuúba (Virola surinamensis) in the presence of cadmium with the perspective of the ...
DOI:
10.1186/s12870-021-02912-y