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3′-Deoxynucleosides have demonstrated profound biochemical utility, including in our recent work on the use of aminoacyl thio-tRNAs for in vitro translation. Though our preparation of 3′-(2-pyridyldithio)-3′-deoxyadenosine—a key synthetic precursor en route to aminoacyl thio-tRNAs—followed robust prior precedents, an unrelated recent structural revision prompted us to validate the regioselectivity of our route further. Here we provide confirmatory evidence for the structure of 3′-(2-pyridyldithio)-3′-deoxyadenosine and downstream analogues via synthetic convergence with a 3′-deoxynucleoside antibiotic, cordycepin, and concomitant MicroED analysis. 

Other: Related Article: Taylor L. Dover, Jacob G. Robins, Brandon Q. Mercado, Alanna Schepartz, Scott J. Miller|2025|J.Org.Chem.|90|9295|doi:10.1021/acs.joc.5c00954 Abstract: An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures. 

Thioesters are critical chemical intermediates in numerous extant biochemical reactions and are invoked as key reagents during prebiotic peptide synthesis on an evolving Earth. Here we asked if a thioester could replace the native oxo-ester in acyl-tRNA substrates during protein biosynthesis by the ribosome. We prepared 3′-thio-3′-deoxyadenosine triphosphate in 10 steps from xylose and demonstrated that it is an effective substrate for the Escherichia coli CCA-adding enzyme, which appends 3′-thio-3′-deoxyadenosine to truncated tRNAs ending with 3′-CC. Using a variety of aminoacyl-tRNA synthetases, flexizymes, or a direct thioester exchange reaction, we prepared a suite of 3′-thio-tRNAs acylated with α- and non-α-amino acids. All were recognized and utilized by wild-type E. coli ribosomes during in vitro translation reactions to generate oligopeptides in yields commensurate with native oxo-ester tRNAs. These results indicate that thioester intermediates widely used in Nature can be co-opted to support the incorporation of natural α-amino acids as well as noncanonical monomers by the extant translational machinery for sequence-defined polymer synthesis. 

Abstract Implant‐associated complications—including infection, adverse immune responses, and poor tissue integration—pose significant risks to patients, often leading to implant failure, revision surgeries, or chronic disease. Current chemical‐based strategies, such as antibiotic or drug‐releasing systems, are limited by short‐term efficacy, narrow therapeutic windows, and potential toxicity. Surface topography offers a promising alternative, but most designs target single cell types and overlook the complex, multicellular dynamics at the implant–host interface. Here, a new multifunctional platform is introduced based on nano–micro hybrid wrinkled topographies fabricated via a custom nanofabrication method that combines layer‐by‐layer (LbL) self‐assembly with mechanical nanomanufacturing. This system simultaneously modulates bacteria, immune cells, and tissue progenitors to enable antibacterial activity, immune regulation, and tissue regeneration. On hybrid surfaces, nanoscale features disrupt bacterial adhesion (>50% biofilm reduction vs. flat controls), while microscale features enhance macrophage polarization (≈3‐fold increase in M2 markers) and osteogenic differentiation (>8‐fold increase in ALP activity), indicating strong pro‐healing responses. Notably, macrophages exhibit context‐dependent behavior—driving inflammation during bacterial infection and repair in its absence—creating an immune‐balanced microenvironment for implant integration. The modular nature of this platform allows expansion to other cell types and disease contexts, offering a broadly applicable strategy for next‐generation biomaterials. 

Abstract: Thioesters are critical chemical intermediates in numerous extant biochemical reactions and are invoked as key reagents during prebiotic peptide synthesis on an evolving Earth. Here we asked if a thioester could replace the native oxo-ester in acyl-tRNA substrates during protein biosynthesis by the ribosome. We prepared 3′-thio-3′-deoxyadenosine triphosphate in 10 steps from xylose and demonstrated that it is an effective substrate for the E. coli CCA-adding enzyme, which appends 3′-thio-3′-deoxyadenosine to truncated tRNAs ending with 3′-CC. Using a variety of aminoacyl-tRNA synthetases, flexizymes, or a direct thioester exchange reaction, we prepared a suite of 3′-thio-tRNAs acylated with α- and non-α-amino acids. All were recognized and utilized by wild-type Escherichia coli ribosomes during in vitro translation reactions to generate oligopeptides in yields commensurate with native oxo-ester tRNAs. These results indicate that thioester intermediates widely used in Nature can be co-opted to support the incorporation of natural α-amino acids as well as non-canonical monomers by the extant translational machinery for sequence-defined polymer synthesis. 

Abstract (Diene)Rh(I) complexes catalyze the stereoselective three‐component coupling of silyl glyoxylates, arylboronic acids, and aldehydes to give glycolate aldol products. The participation of Rh‐alkoxides in the requisite Brook rearrangement was established through two component Rh‐catalyzed couplings of silyl glyoxylates with ArB(OH)₂to give silyl‐protected mandelate derivatives. The intermediacy of a chiral Rh‐enolate was inferred through enantioselective protonation using a chiral Rh‐catalyst. Diastereoselective three‐component couplings with aldehydes as terminating electrophiles to give racemic products were best achieved with a bulky aryl ester on the silyl glyoxylate reagent. Optimal enantioselective couplings were carried out with thetert‐butyl ester variant using an anisole‐derived enantiopure tricyclo[3.2.2.0^2,4]nonadiene ligand.