This review summarizes the advances in catalytic enantioselective reactions using CO ₂ as a C1 synthon, introduces strategies and discusses advantages and limitations, highlights the application, and outlines the synthetic opportunities.

Pentacyclic triterpenoids, as important representatives of natural products, have garnered widespread attention due to their diverse biological activities, including anti-inflammatory, antiviral, and antitumor effects. Oleanolic acid (OA), betulinic acid (BA), ursolic acid (UA), triptolide, and glycyrrhetinic acid (GA) are typical examples of pentacyclic triterpenoids. Despite their significant biological activities, their poor water solubility and low bioavailability have limited further development and application. In recent years, researchers have developed a series of derivatives with enhanced biological activities and improved drug properties through structural modifications of these compounds, particularly achieving notable progress in the field of antitumor therapy. This review summarizes recent advances in the structural modification of pentacyclic triterpenoids and explores their promising applications in the development of antitumor, antiviral, and other therapeutic agents.

This feature article aims to summarize the exciting advances in organocatalytic enantioselective reactions involving prochiral carbocationic intermediates.

Pancreatic cancer is a concealed and highly malignant tumor, and its early diagnosis plays an increasingly weighty role during the course of cancer treatment. In this study, we developed a polymeric magnetic resonance imaging (MRI) nanoplatform for MRI contrast agents. To improve tumor-targeting delivery of MRI contrast agents, we employed a pancreatic cancer targeting CKAAKN peptide to prepare a peptide-functionalized amphiphilic hyaluronic acid–vitamin E succinate polymer (CKAAKN–HA–VES) for delivering ultra-small superparamagnetic iron oxide (USPIO), namely, CKAAKN–HA–VES@USPIO. With the modification of the CKAAKN peptide, CKAAKN–HA–VES@USPIO could specifically internalize into CKAAKN-positive BxPC-3 cells. The CKAAKN–HA–VES@USPIO nanoparticles presented a more specific accumulation into pancreatic cancer cells than normal pancreatic cells, and an obvious decrease in signal intensity was observed in CKAAKN-positive BxPC-3 cells, compared with CKAAKN-negative HPDE6-C7 cells and non-targeting HA–VES@USPIO nanoparticles. The results demonstrated that our polymeric MRI nanoplatform could selectively internalize into CKAAKN-positive pancreatic cancer cells by the specific binding of CKAAKN peptide with pancreatic cancer cell membrane receptors, which provided a novel polymeric MRI contrast agent with high specificity for pancreatic cancer diagnosis, and makes it a very promising candidate for magnetic resonance imaging contrast enhancement.