Urinary D-amino acid profiles in cats with chronic kidney disease.

Chronic kidney disease (CKD) is highly prevalent in domestic cats. This study aimed to compare urinary D-amino acid levels between control and CKD-afflicted cats as a novel noninvasive method for assessing CKD.Cats were divided into control and CKD stage II groups in accordance with the International Renal Interest Society guidelines. The urinary DL-amino acid levels of the cats were analyzed using chiral tandem liquid chromatography-tandem mass spectrometry, and their medical records were investigated. The CKD group had considerably lower urinary D-amino acid concentrations and enantiomeric ratios than the control group. The total urinary D-amino acid contents significantly correlated with blood parameters (creatinine and urea nitrogen). These findings may contribute towards the detection of CKD stage II in domestic cats.

Asymmetric total synthesis of (-)-leuconoxine via chiral phosphoric acid catalyzed desymmetrization of a prochiral diester.

The asymmetric total synthesis of (-)-leuconoxine has been achieved. The desymmetrization of a prochiral diester using a chiral phosphoric acid catalyst produced a highly enantioenriched lactam with excellent yield. The ring construction featuring an intramolecular N-acyliminium cyclization and the one-step pyrrolidone formation using Bestmann's ylide was successfully accomplished.