2140-95-6Relevant articles and documents
Catalytic Asymmetric Synthesis of Unprotected β2-Amino Acids
Zhu, Chendan,Mandrelli, Francesca,Zhou, Hui,Maji, Rajat,List, Benjamin
supporting information, p. 3312 - 3317 (2021/04/07)
We report here a scalable, catalytic one-pot approach to enantiopure and unmodified β2-amino acids. A newly developed confined imidodiphosphorimidate (IDPi) catalyzes a broadly applicable reaction of diverse bis-silyl ketene acetals with a silylated aminomethyl ether, followed by hydrolytic workup, to give free β2-amino acids in high yields, purity, and enantioselectivity. Importantly, both aromatic and aliphatic β2-amino acids can be obtained using this method. Mechanistic studies are consistent with the aminomethylation to proceed via silylium-based asymmetric counteranion-directed catalysis (Si-ACDC) and a transition state to explain the enantioselectivity is suggested on the basis of density functional theory calculation.
Absolute Configuration and Antibiotic Activity of Piceamycin
Beom, Ji Yoon,Byun, Woong Sub,Chung, Beomkoo,Hong, Suckchang,Jeon, Chang-Wook,Kang, Saeyeon,Kwak, Youn-Sig,Lee, Jeeyeon,Lee, Sang Kook,Oh, Dong-Chan,Oh, Ki-Bong,Shin, Jongheon,Shin, Yern-Hyerk,Yoon, Yeo Joon
, (2020/03/04)
The cultivation of a Streptomyces sp. SD53 strain isolated from the gut of the silkworm Bombyx mori produced two macrolactam natural products, piceamycin (1) and bombyxamycin C (2). The planar structures of 1 and 2 were identified by a combination of NMR, MS, and UV spectroscopic analyses. The absolute configurations were assigned based on chemical and chromatographic methods as well as ECD calculations. A new chromatography-based experimental method for determining the configurations of stereogenic centers β to nitrogen atoms in macrolactams was established and successfully applied in this report. These compounds exhibited significant bioactivities against the silkworm entomopathogen Bacillus thuringiensis and various human pathogens as well as human cancer cell lines. In particular, piceamycin potently inhibited Salmonella enterica and Proteus hauseri with MIC values of 0.083 μg/mL and 0.025 μg/mL, respectively. The biosynthetic pathway involved in the formation of the cyclopentenone moiety in piceamycin is discussed.
Modular Enzymatic Cascade Synthesis of Vitamin B5 and Its Derivatives
Abidin, Mohammad Z.,Saravanan, Thangavelu,Zhang, Jielin,Tepper, Pieter G.,Strauss, Erick,Poelarends, Gerrit J.
supporting information, p. 17434 - 17438 (2018/11/10)
Access to vitamin B5 [(R)-pantothenic acid] and both diastereoisomers of α-methyl-substituted vitamin B5 [(R)- and (S)-3-((R)-2,4-dihydroxy-3,3-dimethylbutanamido)-2-methylpropanoic acid] was achieved using a modular three-step biocatalytic cascade involving 3-methylaspartate ammonia lyase (MAL), aspartate-α-decarboxylase (ADC), β-methylaspartate-α-decarboxylase (CrpG) or glutamate decarboxylase (GAD), and pantothenate synthetase (PS) enzymes. Starting from simple non-chiral dicarboxylic acids (either fumaric acid or mesaconic acid), vitamin B5 and both diastereoisomers of α-methyl-substituted vitamin B5, which are valuable precursors for promising antimicrobials against Plasmodium falciparum and multidrug-resistant Staphylococcus aureus, can be generated in good yields (up to 70 %) and excellent enantiopurity (>99 % ee). This newly developed cascade process may be tailored and used for the biocatalytic production of various vitamin B5 derivatives by modifying the pantoyl or β-alanine moiety.
