Molecular Ratchets and Kinetic Asymmetry: Giving Chemistry Direction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(23)

Опубликована: Апрель 3, 2024

Abstract Over the last two decades ratchet mechanisms have transformed understanding and design of stochastic molecular systems—biological, chemical physical—in a move away from mechanical macroscopic analogies that dominated thinking regarding dynamics in 1990s early 2000s (e.g. pistons, springs, etc), to more scale‐relevant concepts underpin out‐of‐equilibrium research sciences today. Ratcheting has established nanotechnology as frontier for energy transduction metabolism, enabled reverse engineering biomolecular machinery, delivering insights into how molecules ‘walk’ track‐based synthesisers operate, acceleration reactions enables be transduced by catalysts (both motor proteins synthetic catalysts), dynamic systems can driven equilibrium through catalysis. The recognition biology, their invention systems, is proving significant areas diverse supramolecular chemistry, covalent DNA nanotechnology, polymer materials science, heterogeneous catalysis, endergonic synthesis, origin life, many other branches science. Put simply, give chemistry direction. Kinetic asymmetry, key feature ratcheting, counterpart structural asymmetry (i.e. chirality). Given ubiquity processes significance behaviour function it surely just fundamentally important. This Review charts recognition, development ratchets, focussing particularly on role which they were originally envisaged elements machinery. Different kinetically asymmetric are compared, consequences discussed. These archetypal examples demonstrate inexorably equilibrium, rather than relax towards it.

Язык: Английский

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Kinetic Asymmetry and Directionality of Nonequilibrium Molecular Systems

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(9)

Опубликована: Янв. 18, 2024

Abstract Scientists have long been fascinated by the biomolecular machines in living systems that process energy and information to sustain life. The first synthetic molecular rotor capable of performing repeated 360° rotations due a combination photo‐ thermally activated processes was reported 1999. progress designing different intervening years has remarkable, with several outstanding examples appearing last few years. Despite accomplishments, there remains confusion regarding fundamental design principles which motions molecules can be controlled, significant intellectual tension between mechanical chemical ways thinking about describing machines. A thermodynamically consistent analysis kinetics rotors pumps shows while light driven operate power‐stroke mechanism, kinetic asymmetry—the relative heights barriers—is sole determinant directionality catalysis Power‐strokes—the depths wells—play no role whatsoever determining sign directionality. These results, elaborated using trajectory thermodynamics nonequilibrium pump equality, show asymmetry governs response many non‐equilibrium phenomena.

Язык: Английский

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Transducing chemical energy through catalysis by an artificial molecular motor

Nature, Год журнала: 2025, Номер 637(8046), С. 594 - 600

Опубликована: Янв. 15, 2025

Abstract Cells display a range of mechanical activities generated by motor proteins powered through catalysis 1 . This raises the fundamental question how acceleration chemical reaction can enable energy released from that to be transduced (and, consequently, work done) molecular catalyst 2–7 Here we demonstrate molecular-level transduction force 8 in form contraction and re-expansion cross-linked polymer gel driven directional rotation artificial catalysis-driven 9 motors. Continuous 360° rotor about stator motor-molecules incorporated polymeric framework twists chains network around one another. progressively increases writhe tightens entanglements, causing macroscopic approximately 70% its original volume. The subsequent addition opposite enantiomer fuelling system powers reverse direction, unwinding entanglements re-expand. Continued twisting strands new direction causes re-contract. In actuation, motor-molecule produces other physical outcomes, including changes Young modulus storage modulus—the latter is proportional increase strand crossings resulting rotation. experimental demonstration against load synthetic organocatalyst, mechanism 6 , informs both debate 3,5,7 surrounding generation biological motors design principles 6,10–14 for nanotechnology.

Язык: Английский

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Artificial Molecular Ratchets: Tools Enabling Endergonic Processes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(47)

Опубликована: Авг. 7, 2023

Abstract Non‐equilibrium chemical systems underpin multiple domains of contemporary interest, including supramolecular chemistry, molecular machines, prebiotic and energy transduction. Experimental chemists are now pioneering the realization artificial that can harvest away from equilibrium. In this tutorial Review, we provide an overview ratchets: mechanisms enabling absorption environment. By focusing on mechanism type—rather than application domain or source—we offer a unifying picture seemingly disparate phenomena, which hope will foster progress in fascinating science.

Язык: Английский

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Ratcheting synthesis

Nature Reviews Chemistry, Год журнала: 2023, Номер 8(1), С. 8 - 29

Опубликована: Дек. 15, 2023

Язык: Английский

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Conformational selection accelerates catalysis by an organocatalytic molecular motor

Chem, Год журнала: 2023, Номер 10(3), С. 855 - 866

Опубликована: Ноя. 22, 2023

Conformational dynamics are increasingly recognized as an important contributor to enzyme catalysis but often overlooked in synthetic catalyst design. Here, we experimentally demonstrate faster by conformational selection caused stochastic interconversion of two conformations a catenane-based organocatalyst. The dependencies the reaction rates on relative positioning components during different stages catalytic cycle enable dynamic organocatalyst achieve order-of-magnitude rate accelerations over static or predominantly single-conformer analogs. acceleration results emergent property acting directionally rotating motor. In demonstrating that can overcome linear scaling relationships, these findings have implications for theories and artificial link between biased may suggest "motor molecules" could first arisen primitive form due prebiotic evolutionary pressure catalysis.

Язык: Английский

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Endergonic synthesis driven by chemical fuelling

Nature Synthesis, Год журнала: 2024, Номер 3(6), С. 707 - 714

Опубликована: Март 11, 2024

Abstract Spontaneous chemical reactions proceed energetically downhill to either a local or global minimum, limiting possible transformations those that are exergonic. Endergonic do not spontaneously and require an input of energy. Light has been used drive number deracemizations thermodynamically unfavourable bond-forming reactions, but is restricted substrates can absorb, directly indirectly, energy provided by photons. In contrast, anabolism involves uphill powered fuels. Here we report on the transduction from artificial fuel Diels–Alder reaction. Carboxylic acid catalysed carbodiimide-to-urea formation chemically orthogonal reaction diene dienophile, transiently brings functional groups into close proximity, causing otherwise prohibited cycloaddition in modest yield (15% after two fuelling cycles) with high levels regio- (>99%) stereoselectivity (92:8 exo : endo ). Kinetic asymmetry cycle ratchets away equilibrium distribution Diels–Alder:retro-Diels–Alder products. The driving endergonic occurs through ratchet mechanism (an information ratchet, depending synthetic protocol), reminiscent how molecular machines directionally bias motion. Ratcheting synthesis potential expand chemistry toolbox terms reactivity, complexity control.

Язык: Английский

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Structural Influence of the Chemical Fueling System on a Catalysis-Driven Rotary Molecular Motor

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Фев. 27, 2025

Continuous directionally biased 360° rotation about a covalent single bond was recently realized in the form of chemically fueled 1-phenylpyrrole 2,2′-dicarboxylic acid rotary molecular motor. However, original fueling system and reaction conditions resulted motor directionality only ∼3:1 (i.e., on average backward for every three forward rotations), along with catalytic efficiency operation 97% fuel 14%. Here, we report efficacy series chiral carbodiimide fuels hydrolysis promoters (pyridine pyridine N-oxide derivatives) driving improved directional this motor-molecule. We outline complete network operation, composed directional, futile, slip cycles. Using derivatives where final conformational step is either very slow or completely blocked, phenylpyrrole diacid becomes enantiomerically enriched, allowing kinetic gating individual steps cycle to be measured. The that produces highest gives 13% enantiomeric excess (e.e.) anhydride-forming kinetically gated step, while most effective promoter generates 90% e.e. step. Combining best-performing into results 92% e.e.. Under dilute chemostated regime (to avoid N-acyl urea formation at high concentrations promoters), continuously rotates ∼24:1 24 rotations) >99% 51%.

Язык: Английский

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Stepwise Operation of a Molecular Rotary Motor Driven by an Appel Reaction

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(7), С. 4467 - 4472

Опубликована: Фев. 6, 2024

To date, only a small number of chemistries and chemical fueling strategies have been successfully used to operate artificial molecular motors. Here, we report the 360° directionally biased rotation phenyl groups about C–C bond, driven by stepwise Appel reaction sequence. The motor molecule consists biaryl-embedded phosphine oxide phenol, in which full around biaryl bond is blocked P–O oxygen atom on rotor being too bulky pass stator. Treatment with SOCl2 forms cyclic oxyphosphonium salt (removing oxide), temporarily linking Conformational exchange via ring flipping then allows stator twist back forth past previous limit rotation. Subsequently, opening tethered intermediate chiral alcohol occurs preferentially through nucleophilic attack one face. Thus, original reformed net directional over course two-step Each repetition SOCl2–chiral additions generates another Using same sequence derivative that atropisomers rather than fully rotating results enantioenrichment, suggesting that, average, rotates "wrong" direction once every three cycles. interconversion oxides form temporary tethers enable rotational barrier be overcome adds available for generating chemically fueled kinetic asymmetry systems.

Язык: Английский

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Artificial molecular pumps

Nature Reviews Methods Primers, Год журнала: 2024, Номер 4(1)

Опубликована: Фев. 22, 2024

Язык: Английский

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