Synthesis of Unprotected 2-Arylglycines by Transamination of Arylglyoxylic Acids with 2-(2-Chlorophenyl)glycine

Arylation of Diethyl Acetamidomalonate with Diaryliodonium Salts En Route to α-Arylglycines

Diethyl acetamidomalonate (DEAM) has been widely used for the synthesis of α-amino acids via C-alkylation under basic conditions followed by hydrolysis/decarboxylation. In contrast, the C-arylation of this reagent remains undeveloped. Herein, we report a novel strategy for the synthesis of racemic α-arylglycines based on the selective arylation of DEAM with diaryliodonium salts under mild, transition metal-free conditions. The reaction features good functional group tolerance and easy scalability and is applicable to the chemoselective C-H-modification of arenes including approved drugs, thus enabling a straightforward approach to complex α-arylglycines that would be challenging to make otherwise.

Anti-Aging Constituents from Pinus morrisonicola Leaves

Pinus morrisonicola Hayata is a unique plant species found in Taiwan. Previous studies have identified its anti-hypertensive, anti-oxidative, and anti-inflammatory effects. In this study, a bioactivity-guided approach was employed to extract 20 compounds from the ethyl acetate fraction of the ethanol extract of Pinus morrisonicola Hayata's pine needles. The anti-aging effects of these compounds were investigated using HT-1080 cells. The structures of the purified compounds were confirmed through NMR and LC-MS analysis, revealing the presence of nine flavonoids, two lignans, one coumarin, one benzofuran, one phenylic acid, and six diterpenoids. Among them, PML18, PML19, and PML20 were identified as novel diterpene. Compounds 3, 4, and 5 exhibited remarkable inhibitory effects against MMP-2 and showed no significant cell toxicity at 25 μM. Although the purified compounds showed lower activity against Pro MMP-2 and Pro MMP-9 compared to the ethyl acetate fraction, we speculate that this is the result of synergistic effects.

Photoinduced homolytic decarboxylative acylation/cyclization of unactivated alkenes with α-keto acid under external oxidant and photocatalyst free conditions: access to quinazolinone derivatives

A novel and green strategy for the synthesis of acylated quinazolinone derivatives via photo-induced decarboxylative cascade radical acylation/cyclization of quinazolinone bearing unactivated alkenes has been developed. The protocol provides a novel route to access acyl radicals from α-keto acids through a self-catalyzed energy transfer process. Most importantly, the reaction proceeded smoothly without any external photocatalyst, additive or oxidant, and could be easily scaled-up in flow conditions with sunlight irradiation.