Intermolecular C−C bond-forming reactions are underdeveloped transformations in the field of biocatalysis. Here we report a photoenzymatic intermolecular hydroalkylation of olefins catalyzed by flavin-dependent 'ene'-reductases. Radical initiation occurs via photoexcitation of a rare high-order enzyme-templated charge-transfer complex that forms between an alkene, αchloroamide, and flavin hydroquinone. This unique mechanism ensures that radical formation only occurs when both substrates are present within the protein active site. This active site can control the radical terminating hydrogen atom transfer, enabling the synthesis of enantioenriched γ-stereogenic amides. This work highlights the potential for photoenzymatic catalysis to enable new biocatalytic transformations via previously unknown electron transfer mechanisms.

Background Falls are the leading cause of injuries among older adults, and trips and slips are major contributors to falls. Objective The authors sought to compare the effectiveness of adding a component of surface perturbation training to usual gait/balance training for reducing falls and fall-related injury in high-risk older adults referred to physical therapy. Design This was a multi-center, pragmatic, randomized, comparative effectiveness trial. Setting Treatment took place within 8 outpatient physical therapy clinics. Patients This study included 506 patients 65+ years of age at high fall risk referred for gait/balance training. Intervention This trial evaluated surface perturbation treadmill training integrated into usual multimodal exercise-based balance training at the therapist’s discretion versus usual multimodal exercise-based balance training alone. Measurements Falls and injurious falls were assessed with a prospective daily fall diary, which was reviewed via telephone interview every 3 months for 1 year. A total of 211/253 (83%) patients randomized to perturbation training and 210/253 (83%) randomized to usual treatment provided data at 3-month follow-up. At 3 months, the perturbation training group had a significantly reduced chance of fall-related injury (5.7% versus 13.3%; relative risk 0.43) but no significant reduction in the risk of any fall (28% versus 37%, relative risk 0.78) compared with usual treatment. Time to first injurious fall showed reduced hazard in the first 3 months but no significant reduction when viewed over the entire first year. Limitations The limitations of this trial included lack of blinding and variable application of interventions across patients based on pragmatic study design. Conclusion The addition of some surface perturbation training to usual physical therapy significantly reduced injurious falls up to 3 months posttreatment. Further study is warranted to determine the optimal frequency, dose, progression, and duration of surface perturbation aimed at training postural responses for this population.

A strategy for controlling relative placements of molecules within multicomponent monolayers at the solution-HOPG interface is demonstrated. The monolayers assemble from complementary pairs of 1,5-bis-alkyldiether-anthracenes bearing self-repelling side chains. Each diether side chain suffers repulsive dipolar interactions if it adsorbs next to an identical side chain in the morphology normally assumed by 1,5-bis-substituted-anthracene monolayers. Complementary side-chain pairs experience attractive dipolar interactions when adsorbed as neighbors in the normal morphology monolayer. The repulsive and attractive forces spontaneously drive formation of a patterned monolayer at the solution-HOPG interface. Each molecule adsorbs in its own row, sandwiched between two rows of the complementary anthracene. These studies demonstrate the viability of using weak dipolar interactions to control molecular placement and monolayer morphology and to pattern multicomponent monolayers.

[Rh(CO)2Cl]2 is as an effective catalyst for endo-selective cyclizations and cascades of epoxy-(E)-enoate alcohols, thus enabling the synthesis of oxepanes and oxepane-containing polyethers from di- and trisubstituted epoxides. Syntheses of the ABC and EF ring systems of (−)-brevisin via all endo-diepoxide-opening cascades using this method constitute a formal total synthesis and demonstrate the utility of this methodology in the context of the synthesis of marine ladder polyether natural products.