Article
Chemistry, Organic
Sarah E. Luderer, Behrad Masoudi, Aritra Sarkar, Calvin Grant, Arvind Jaganathan, James E. Jackson, Babak Borhan
Summary: Various structural elements of Cinchona alkaloid dimers were studied to establish a structure-enantioselectivity relationship (SER) in three different halocyclization reactions. The sensitivity of SER to linker rigidity and polarity, alkaloid structure, and the presence of alkaloid side groups defining the catalyst pocket varied in the chlorocyclizations. DFT calculations on methoxylated models revealed high barriers to ether rotation, indicating the importance of conformational rigidity in linker-ether connections.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Kazuki Fujita, Masataka Miura, Yasuhiro Funahashi, Tsubasa Hatanaka, Shuichi Nakamura
Summary: The enantioselective reaction of 2H-azirines with oxazol-S-(4H)-ones using a cinchona alkaloid sulfonamide catalyst has been developed, producing products with consecutive tetrasubstituted stereogenic centers in high yield with high diastereo- and enantioselectivity. The obtained aziridines were converted into various chiral compounds without loss of enantiopurity.
Article
Chemistry, Physical
Mariola Zielinska-Blajet, Joanna Najdek
Summary: An efficient approach to synthesizing chiral selenoureas derived from Cinchona alkaloid scaffolds was described in this study. These selenoureas were evaluated as bifunctional organocatalysts in asymmetric Michael addition reactions, with the best results achieved by those containing the 4-fluorophenyl group, showing enantioselectivities up to 96% ee. Additionally, the catalytic performance of thiourea and selenourea counterparts was compared.
Article
Chemistry, Organic
Hao Sun, Pinli Dai, Jie Tian, Qian Xu, Qian Chen, Linlin Li, Xin Meng, Lin Zhang, Chun Li
Summary: A variety of NN ligands derived from cinchona alkaloids with N-H groups were used for the asymmetric hydrogenation of ketones. Substituting the N-H group of the ligands showed that it was essential for asymmetric hydrogenation, as without it the reaction could not proceed. The optimal ligand demonstrated high enantioselectivity (up to 98.8% ee) and good yields for various aromatic and α,β-unsaturated ketones.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Infectious Diseases
Alma Ramic, Mirjana Skocibusic, Renata Odzak, Ana Cipak Gasparovic, Lidija Milkovic, Ana Mikelic, Karlo Sovic, Ines Primozic, Tomica Hrenar
Summary: A series of N-substituted quaternary salts of cinchonidine were prepared and evaluated for their antimicrobial activity, showing good potential against a diverse panel of bacteria. By establishing an activity/potential energy surface model, accurate predictions of activity for new compounds can be made based solely on their potential energy surfaces, facilitating the search for new potential antibiotics.
Article
Chemistry, Multidisciplinary
Rong Chen, Cangjie Yang, Zefeng Zhou, Fredrik Haeffner, Alinda Dersjant, Nicholas Dulock, Qi Dong, Da He, Jing Jin, Yanyan Zhao, Jia Niu, Dunwei Wang
Summary: An electrochemical method for coupling biomass-derived C5/C6 compounds to value-added fuel precursors was reported. The reaction, which is not sensitive to oxygen and can be promoted by a trace amount of water, achieves high yield in a single step. Mechanistic studies confirmed radical generation through electrochemistry as the key to the reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Medicinal
Alma Ramic, Ana Matosevic, Barbara Debanic, Ana Mikelic, Ines Primozic, Anita Bosak, Tomica Hrenar
Summary: A series of Cinchona alkaloid derivatives were synthesized and tested for their inhibitory activity against human acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The results showed that these compounds could reversibly inhibit AChE and BChE in the nanomolar to micromolar range. Among them, N-(meta-fluorobenzyl)cinchonidinium bromide exhibited the highest selectivity for BChE, with 533 times higher preference than AChE. The creation of multivariate linear regression models using machine learning techniques provided a valuable tool for identifying new potential leads.
Article
Chemistry, Physical
Zhiping Che, Song Zhang, Yihao Guo, Yibo Liu, Ruxue Wei, Lin Zhou, Xiaobo Huang, Shengming Liu, Genqiang Chen, Yuee Tian
Summary: Twenty cinchona alkaloid carbamate derivatives were designed, synthesized, and confirmed by various techniques. Five of these compounds exhibited significant anti-fungal and anti-oomycete activities in vitro. Substituents in the cinchona alkaloid skeleton, specifically R1/R2 = Ph/Ph, were found to play a crucial role in determining the activity. Additionally, the configuration of the C8/9 position of the target compound was found to be important, with the 9S configuration being optimal.
JOURNAL OF MOLECULAR STRUCTURE
(2023)
Article
Chemistry, Multidisciplinary
Jialin Qi, Fang Wei, Shuai Huang, Chen-Ho Tung, Zhenghu Xu
Summary: A new method has been developed for the synthesis of sulfur-containing chiral beta-lactams with two consecutive stereogenic centers using copper(I)-catalyzed asymmetric, three-component interrupted Kinugasa reaction. The key lies in the interception of in situ formed chiral four membered copper(I) enolate intermediate with sulfur electrophiles, resulting in good yields and excellent diastereo- and enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Donghui Guo, Jian Wang
Summary: An unprecedented organic catalyzed transamination reaction strategy has been developed for the high-yield synthesis of axial chiral biaryls. This method has a broad substrate applicability and can prepare compounds with potential catalytic applications.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Laila A. Al-Mutabagani, Latifah A. Alshabanah, Sobhi M. Gomha, Tariq Z. Abolibda, Mohamed Shaban, Hoda A. Ahmed
Summary: The new homologues of liquid crystalline materials based on furfural derivatives exhibited purely nematic mesophase, with the longest chain derivative showing a dimorphic phase. The incorporation of the furfural ring affected the mesophase range and stability. The shortest chain compound had two direct band gaps and higher absorption compared to the longer homologues. All synthesized homologues showed Ohmic behaviors with electrical resistances in the G omega range.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Organic
Mohammad Farhadur Rahman, Chouthor Yangyuayang, Ikuhide Fujisawa, Naoki Haraguchi, Shinichi Itsuno
Summary: The C5'-nitro-dihydroquinine (Q1), derived from dihydroquinine (HQ), exhibited superior catalytic activity and asymmetric induction in an asymmetric Michael reaction.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Aimar Gonzalo-Barquero, Benedicte Lepoittevin, Jacques Rouden, Jerome Baudoux
Summary: A simple and rapid access to fluorinated dithioesters was developed using a one-pot sequence of Grignard reaction-Mitsunobu type substitution. These activated dithioesters exhibited excellent reactivity in aminolysis reactions, allowing the synthesis of various thioamides, including a 4-styrenylthioamide cinchonidine monomer, under environmentally friendly conditions, at room temperature, and in a very short time.
Article
Agriculture, Multidisciplinary
Tomais Herraiz, Adriana Pena, Antonio Salgado
Summary: This research identifies and characterizes perlolyrine, a beta-carboline compound with a furan moiety, and reveals its formation mechanism and occurrence in various foods. Perlolyrine is formed from the reaction of L-tryptophan with 3-deoxyglucosone, an intermediate of carbohydrate degradation, under acidic conditions and temperatures in the range of 70-110 degrees C. It is widely present in processed foods and is ingested daily through the diet.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Article
Agriculture, Multidisciplinary
Tomais Herraiz, Adriana Pena, Antonio Salgado
Summary: Perlolyrine is a naturally occurring compound found in many foods. It is formed from the reaction of L-tryptophan with carbohydrates and is generated during the heating process. The highest concentrations of perlolyrine are present in tomato concentrate and soy sauce, and it is ingested daily through diet.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
