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Coordination‐Driven Direct C─H Metalation of <i>N</i> ‐Heterocycles With a Superbasic Co(II) Amide Co(TMP) ₂

ABSTRACT Metalation of N ‐heterocycles such as pyridines or diazines with conventional alkali metal bases is particularly challenging due to the limited activation of their C─H bonds coupled with the thermal fragility of the resulting organometallic intermediates. Building upon previous work in this area, we demonstrate that the superbasic cobalt(II) amide Co(TMP) 2 (TMP = 2,2,6,6‐tetramethylpiperidide) enables high‐yielding and highly regioselective C─H metalation of a broad range of N ‐heterocycles via direct, redox‐neutral Co(II)–H exchange. This reactivity extends beyond single‐site activation, with controlled di‐cobaltation of non‐activated substrates such as pyrimidine and pyrazine. Via a combination of NMR reaction monitoring, isolation and characterisation of key organometallic intermediates, and density functional theory calculations, we establish that regioselectivity is dictated by coordination effects at positions α to nitrogen, overriding conventional trends based solely on C─H acidity. Exploiting cobalt's redox flexibility, oxidative treatment of the metalated intermediates with iodine enables selective C─N bond formation, giving sterically demanding TMP‐substituted heterocycles. Collectively, these findings establish Co(TMP) 2 as a mechanistically distinct and versatile reagent for the selective functionalisation of N ‐heterocycles.

Meaningful ciphertext encryption for color image via 2D-CICCM and stairwise compression

Engineering Crystalline Frameworks into Porous Liquids to Fabricate Graphene Oxide/Porous Liquid Membranes for Efficient Li+/Mg2+ Separation

Diastereodivergent Hydroamidation of Methylenecyclohexanes With Differentiated Active Catalytic Species

ABSTRACT The construction of three‐dimensional (3D) organic molecular structures is pivotal in modern organic chemistry. For three dimensionally structured disubstituted cyclohexanes, which exist as two possible configurations ( cis ‐ and trans ‐), substituent orientation dictates thermodynamic stability, physicochemical properties, and biological activities, but precise stereocontrol of cycloalkane substituents is challenging. Herein, we report the diastereodivergent hydroamidation of methylenecyclohexanes: a nickel catalytic system efficiently synthesizes 1,4‐ cis / trans and 1,3‐ cis / trans isomers, while a cobalt system realizes 1,2‐ cis / trans stereodivergence. The core achievement lies in a strategy utilizing differentiated active catalytic species, which enables the precise regulation of the spatial structure and electronic properties of metal‐hydride or metal‐functional group intermediates. This work broadens the chemical space for multi‐substituted cyclohexane synthesis, provides a powerful tool for the preparation of cycloalkyl‐containing drug molecules, and offers an important case for research on substituted cyclohexane stereochemistry.

Robust artificial intelligence frameworks for lung cancer subtyping and malignancy detection on thoracic CT

An invariant VLR-like receptor refines the T-like cell framework in lamprey

Qing Tang

Fused‐Ring Acceptor–π–Acceptor Architecture Enables Near‐Infrared‐Absorbing Mesoporous Covalent Organic Frameworks for Enhanced H ₂ O ₂ Photosynthesis

ABSTRACT Covalent organic frameworks (COFs) featuring donor–acceptor architectures have shown great promise as photocatalysts. However, their performance is often hindered by limitations such as narrow absorbance ranges and restricted electron delocalization, which are inherent to traditional imine linkages. Herein, we introduce a fused‐ring acceptor–π–acceptor (FRA–π–A) architecture for near‐infrared‐absorbing COFs, enabled via in situ COF‐to‐COF transformation that replaces imine linkages with FRA‐derived benzodithiazoles (or benzodioxazoles). Comprehensive structural characterizations confirm their mesoporous crystalline structure, featuring pore size distribution of 2.16–2.39 nm and broad light absorption extending to near‐infrared region. Property investigations demonstrate that the rigid backbones derived from the FRA–π–A architecture significantly enhance long‐range in‐plane electron delocalization, thereby improving the separation and transport of photogenerated charge carriers. Crucially, the accelerated carrier migration preferentially directs photogenerated electrons to the FRAs, promoting the formation of •O 2 − radicals and accelerating the rate‐limiting step of the oxygen reduction reaction. These synergistic structural and optoelectronic properties endow the FRA–π–A COFs with an outstanding photocatalytic H 2 O 2 production rate of 6.8 mmol g − 1 h − 1 without sacrificial agents, exceeding the vast majority of conjugated linkage‐based COFs. This study highlights the immense potential of FRA–π–A COFs as high‐performance photocatalysts.

Effectiveness of micro-exercises for managing neck/shoulder pain in sedentary workers: a systematic review and meta-analysis

Single-cell map of the healthy human immune system across the lifespan reveals unique infant immune signatures

Positional Isomerism Controls Polarity and Nonlinear Optical Properties in One‐Dimensional Hybrid Germanium Halides

ABSTRACT Organic–inorganic hybrid perovskites (OIHPs) exhibit abundant electronic configurations and structural versatility, rendering them promising candidates for photovoltaic and optoelectronic applications. Despite significant progress in optimizing the structural characteristics of organic cations and inorganic frameworks, the role of cations in determining the electronic structure and nonlinear optical properties has long been underappreciated and remains unclear. We report herein three one‐dimensional germanium‐halide perovskites, AGeI 3 , templated by methylimidazolium cation (A = 1‐Mim/2‐Mim/4‐Mim) positional isomers. Controlling the methyl substitution site on the organic cation can engineer polar structures with distinctly different key optical properties, such as second‐harmonic generation (SHG) and birefringence. (1‐Mim)GeI 3 exhibits the strongest powder SHG response of the OIHP crystals (13 × KH 2 PO 4 @1200 nm) and significant birefringence (0.263 @546 nm). Structural analyses and first‐principles calculations reveal that the SHG response originates from synergism between the [GeI 6 ] and π‐conjugated [C 4 N 2 H 7 ] units, with the unprecedented SHG enhancement in (1‐Mim)GeI 3 being primarily attributed to the asymmetric electron distribution arising from N1‐methyl substitution that enables the favorable ordered alignment of the π‐conjugated 1‐Mim. Our findings not only highlight the critical role of cation positional isomers in controlling physical properties in one‐dimensional hybrid perovskites but also establish one‐dimensional germanium‐iodide perovskites as promising lead‐free candidates for nonlinear optoelectronic applications.

Ultrasound viscosity imaging for stratified diagnosis of diabetic peripheral neuropathy: A prospective clinical study

Continental-scale integration of soil metagenomes and organic matter chemistry reveals ubiquitous microbial capacity for chemically-recalcitrant carbon decomposition

Abstract Soil organic matter (SOM) decomposition by microorganisms is a major uncertainty in predicting terrestrial carbon–atmosphere feedbacks, partly because we lack understanding of the microbial diversity involved in depolymerizing different carbon pools across environmental gradients. We address this gap using a continental-scale dataset pairing shotgun metagenomes with high-resolution SOM chemistry, assembling 0.76 Tbp of prokaryotic MAGs (828 genomes) and identifying 66,727 SOM molecules from 47 standardized U.S. soil cores selected using respiration rates from 106 soils. Integrating these datasets reveals widespread microbial potential for depolymerizing chemically-recalcitrant SOM previously considered stable. We uncover complementary metabolic specialization between genera affiliated with two abundant bacterial orders, Rhizobiales and Chthoniobacterales , and an archaeal order, Nitrososphaerales . This metabolic partitioning is consistent across soil depths and activity levels, suggesting coordinated decomposition of complex SOM through distinct but complementary biochemical strategies. The metabolic potential for depolymerization of chemically-recalcitrant compounds is supported by the abundance of these molecules across the soils, as indicated by Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS), and by flux balance analysis of metabolic models. Our results show that a substantial portion of ostensibly stable SOM remains vulnerable to microbial decomposition, a mechanism not captured in current Earth System Models.

Remarkable Effect of Odd–Even Spacer in Supramolecular Polymerization and Piezoresponse of Amide‐Functionalized Naphthalene Diimides

ABSTRACT This study reports an unprecedented odd–even spacer‐length effect on the supramolecular polymerization and piezoelectricity of a series of amide‐functionalized naphthalene‐diimide (NDI) derivatives. By varying the number of methylene units ( n  = 1–4) in the linker between the NDI‐core and the hydrogen‐bonding amide group, we demonstrate that the parity of the spacer dictates the stability, internal‐order, gelation, and functionality of the supramolecular polymers. Even‐spacer derivatives exhibit significantly higher thermal stability, melting points, and gel‐phase elasticity compared to their odd‐spacer counterparts. Supramolecular polymerization for all derivatives follows a nucleation‐elongation pathway; however, even‐spacer monomers display markedly higher cooperativity and also favor more stable elongation. Molecular dynamics (MD) simulations elucidate the structural origin of these differences: even‐spacer derivatives adopt a tightly packed helical π‐stacking pattern that results in the cancellation of the in‐plane dipoles. In contrast, odd‐spacer derivatives form linear, offset stacking motifs where individual dipoles align and accumulate, leading to highly polarizable supramolecular polymers. This divergence in the internal dipole orientation translates into a dramatic odd–even effect on the piezoelectric dipolar hysteresis. Odd‐spacer derivatives exhibit remarkably high positive piezoelectric coefficients (maximum d 33 ∼ 75 pm/V), whereas even‐spacer systems show much weaker, and rarely reported negative responses (minimum d 33 −15 pm/V).

Metabolic expenditure, neurodevelopment, and weight gain into early childhood after fetal growth restriction

Abstract Fetal growth restriction (FGR) subjects exhibit altered metabolism, with higher metabolic rate due to their small body mass, and by adopting strategies to minimise energy expenditure. We investigated how these metabolic differences develop, or manifest in growth trajectories, after FGR, small for gestational age (SGA) with no evidence of FGR, and normal pregnancies. We curated a unique composite dataset of subjects between 14 weeks of gestation and six years of age. First, we assessed fetal and infant heart rate to assess whether higher metabolic rate persisted postnatally after FGR. Next, as the largest energy expenditure is brain synaptic maintenance, we tested whether FGR infants had lower white matter volume (proxy for synapse number). Finally, we modelled longitudinal body weight into childhood in FGR, SGA, and control groups, and tested for associations with neurodevelopmental scores at 1–2 years. Heart rate at rest was 3.2 beats per minute higher in FGR fetuses and infants (710 subjects), and FGR infants exhibited only 52% the increase in heart rate to a nociceptive procedure (i.e. a physiological challenge) observed in controls. FGR infants had 7 cm 3 smaller white matter volume (270 subjects). Finally, for every − 100 g an individual’s weight deviated below their group’s average (1660 subjects), their motor score was 0.4 points lower (1030 subjects). FGR subjects continue to exhibit metabolic differences long after birth, which may further disadvantage them beyond the initial antenatal insult. Growth trajectories encode information about how FGR is transmitted into suboptimal neurodevelopment, and could identify intervention opportunities.

Structural basis for activation and potentiation in a human α5β3 GABAA receptor

Abstract Anesthetics and anticonvulsants act, in part, through diverse populations of type-A ɣ-aminobutyric acid receptors (GABA A Rs) formed from a pool of 19 subunits. In the hippocampus, α5 subunits primarily coassemble with β3 and, in some cases, γ2, generating numerous subtypes with differential functional and pharmacological properties critical in learning and memory. The stoichiometry, structure, and gating of these subpopulations are poorly understood. Here we show using cryogenic electron microscopy and electrophysiology that the human α5β3 GABA A R predominantly assembles with 2α:3β stoichiometry, though a minority population of 1α:4β indicates multiple assemblies are possible. In a resting-like state, a conserved activation gate and Zn 2+ -coordination at histidines on β3 block ion conduction. Upon GABA binding, global rearrangements release Zn 2+ and open the activation gate in nearly all receptors. The activated receptor is unaffected upon binding the anesthetic etomidate or anticonvulsant topiramate, supporting a conformational selection mechanism of action. This work thus reveals the assembly, activation, and modulation of a GABA A R subtype critical to cognition, providing templates for structure-based drug discovery.

Outside Front Cover: Subsurface Stabilization of Interstitial Pt Atoms on CeO ₂ (111): Rethinking Single‐Atom Catalyst Architectures (Angew. Chem. Int. Ed. 25/2026)

A Kansei-mediated protocol for transforming painting palettes into product aesthetics

Leveraging nanoparticle protein corona to advance plasma proteome profiling

Correspondence on the Correction to “Thermally‐Stable Single‐Site Pd on CeO ₂ Catalyst for Selective Amination of Phenols to Aromatic Amines Without External Hydrogen”