Bridged frameworks are of high chemical and biological significance, being ubiquitous in pharmaceutical molecules and natural products. Specific structures are usually preformed to build these rigid segments at the middle or late stage in the synthesis of polycyclic molecules, resulting in decreased synthetic efficiency and target-specific syntheses. As a logically distinct synthetic strategy, we constructed an allene/ketone-equipped morphan core at the outset through an enantioselective α-allenylation of ketones. Experimental and theoretical results revealed that the high reactivity and enantioselectivity of this reaction are attributed to the cooperative effects of the organocatalyst and metal catalyst. The bridged backbone generated was employed as a structural platform to guide and facilitate the assembly of up to five fusing rings, and the allene and ketone groups thereon were used to precisely install various functionalities at C16 and C20 at the late stage, leading to a concise, collective total synthesis of nine strychnan alkaloids.
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http://dx.doi.org/10.1038/s41557-023-01264-4 | DOI Listing |
World Neurosurg
January 2025
Department of Neurosurgery, Louisiana State University Health Sciences Center at Shreveport, 1501 Kings Highway, Shreveport, LA, 71103.
Background: Recent advances within the last decade have allowed robotics to become commonplace in the operating room. In the field of neurosurgery, robotics assist surgeons in pedicle screw placement and vertebral fusion procedures. The purpose of this review is to look at currently used spinal robots available on the market and compare their overall accuracy, cost, radiation exposure, general adverse events, and hospital readmission rates.
View Article and Find Full Text PDFJ Neurosurg Spine
January 2025
2Cleveland Clinic Center for Spine Health, Cleveland Clinic, Cleveland; and.
Objective: Spinal fusion is a commonly performed surgical procedure used to relieve pain, deformity, and instability of various spinal pathologies. Although there have been attempts to standardize spinal fusion assessment radiologically, there is currently no unified definition that also considers clinical symptomology. This review attempts to create a more holistic and standardized definition of spinal fusion.
View Article and Find Full Text PDFBioengineering (Basel)
January 2025
Department of Software Technology, Konkuk University, Chungju 27478, Republic of Korea.
The timely and accurate detection of brain tumors is crucial for effective medical intervention, especially in resource-constrained settings. This study proposes a lightweight and efficient RetinaNet variant tailored for medical edge device deployment. The model reduces computational overhead while maintaining high detection accuracy by replacing the computationally intensive ResNet backbone with MobileNet and leveraging depthwise separable convolutions.
View Article and Find Full Text PDFOrg Lett
January 2025
Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074, China.
A Cu(I) photoredox-enabled reaction that selectively incorporates a difluoroalkyl group into -aryl glycine derivatives has been established. Using a bench-stable [PhPCFH]Br salt, the -CFH group could be installed either directly on the α-carbon of the glycine backbone or in a three-component fashion using an alkene as a bridge. A series of glycine derivatives have been evaluated, providing access to diverse unnatural amino esters and dipeptides with a -CHF unit.
View Article and Find Full Text PDFNat Chem Biol
January 2025
Department of Gastroenterology, Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Disease, TaiKang Center for Life and Medical Sciences, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, China.
In prokaryotes, the non-bridging oxygen in the DNA sugar-phosphate backbone can be enzymatically replaced by a sulfur atom, resulting in phosphorothioate (PT) modification. However, the mechanism underlying the oxygen-to-sulfur substitution remains enigmatic. In this study, we discovered a hypercompact DNA phosphorothioation system, TdpABC, in extreme thermophiles.
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