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1.
Org Lett ; 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38995695

ABSTRACT

A metal-free cascade of α-acyloxylation/carboxamidation of I(III)/S(VI)-ylides, carboxylic acids, and isonitriles via a Passerini-like multicomponent reaction is reported. Unexpectedly, [3 + 1+1] cyclization involving I(III)/S(VI)-ylides and two molecules of ethyl isocyanoacetate was observed. The strategy allows for the synthesis of unsymmetrical α,α-disubstituted ketones and functionalized pyrroles with up to 99% yield and wide substrate compatibility. Notably, the procedure has been extended to the late-stage modification of drugs and natural products, offering an elegant complement to the classic Passerini reaction.

2.
Org Lett ; 26(27): 5811-5816, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38940397

ABSTRACT

A practical strategy for the construction of diverse phosphonyl and thiofunctionalized sulfoxonium ylides via controllable monofunctionalization of hybrid I(III)/S(VI) ylides is presented. This process allows efficient P-H insertion of I(III)/S(VI) ylides under Cu catalysis, enabling the synthesis of phosphonyl sulfoxonium ylides, whereas reaction with sulfur-containing reagents including AgSCF3, KSC(S)OR, and KSCN under mild conditions resulted in α-trifluoromethylthiolation, dithiocarbanation, and thiocyanation of sulfoxonium ylides accordingly. Of note, wide substrate compatibility (108 examples), excellent efficiency (up to 99% yield), gram-scale experiments, and various product derivatizations highlight the synthetic utility of this protocol.

3.
Chem Commun (Camb) ; 60(51): 6560-6563, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38845542

ABSTRACT

In this study, a Rh(III)-catalyzed C-H/N-H [4+2] annulation of oxadiazolones with iodonium ylides has been developed, which afforded a series of diverse fused-isoquinolines and fused-pyridines in moderate to high yields. These divergent synthesis protocols featured mild conditions, broad substrate scope, and functional-group compatibility. In addition, scale-up synthesis, related applications and preliminary mechanistic explorations were also accomplished.

4.
J Biomech Eng ; 146(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37490328

ABSTRACT

Accurate occupant injury prediction in near-collision scenarios is vital in guiding intelligent vehicles to find the optimal collision condition with minimal injury risks. Existing studies focused on boosting prediction performance by introducing deep-learning models but encountered computational burdens due to the inherent high model complexity. To better balance these two traditionally contradictory factors, this study proposed a training method for pre-crash injury prediction models, namely, knowledge distillation (KD)-based training. This method was inspired by the idea of knowledge distillation, an emerging model compression method. Technically, we first trained a high-accuracy injury prediction model using informative post-crash sequence inputs (i.e., vehicle crash pulses) and a relatively complex network architecture as an experienced "teacher". Following this, a lightweight pre-crash injury prediction model ("student") learned both from the ground truth in output layers (i.e., conventional prediction loss) and its teacher in intermediate layers (i.e., distillation loss). In such a step-by-step teaching framework, the pre-crash model significantly improved the prediction accuracy of occupant's head abbreviated injury scale (AIS) (i.e., from 77.2% to 83.2%) without sacrificing computational efficiency. Multiple validation experiments proved the effectiveness of the proposed KD-based training framework. This study is expected to provide reference to balancing prediction accuracy and computational efficiency of pre-crash injury prediction models, promoting the further safety improvement of next-generation intelligent vehicles.


Subject(s)
Accidents, Traffic , Wounds and Injuries , Humans , Risk , Abbreviated Injury Scale
5.
Chem Commun (Camb) ; 60(5): 598-601, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38099839

ABSTRACT

A new Cp*Rh(III)-catalyzed regioselective cyclization reaction of aromatic amides with allenes is reported. The use of allenyl derivatives bearing a directing-group assistant as a reaction promoter was the key to the success of this protocol. In this catalytic system, N-(pivaloyloxy)benzamide substrates react with allenes via Rh-σ-alkenyl intermediates, while N-(pivaloyloxy) indol substrates react via Rh-π-allyl intermediates. These reactions were characterized by mild reaction conditions, a broad substrate scope, and high functional-group compatibility to yield several high-value isoquinolinone and pyrimido[1,6-a]indol-1(2H)-one skeleton-containing compounds. The synthetic applications and primary mechanisms were also investigated.

6.
BMC Med Inform Decis Mak ; 23(1): 296, 2023 12 20.
Article in English | MEDLINE | ID: mdl-38124086

ABSTRACT

Non-small cell lung cancer (NSCLC) is a malignant tumor that threatens human life and health. The development of a new NSCLC risk assessment model based on electronic medical records has great potential for reducing the risk of cancer recurrence. In this process, machine learning is a powerful method for automatically extracting risk factors and indicating impact weights for NSCLC deaths. However, when the number of samples reaches a certain value, it is difficult for machine learning to improve the prediction accuracy, and it is also challenging to use the characteristic data of subsequent patients effectively. Therefore, this study aimed to build a postoperative survival risk assessment model for patients with NSCLC that updates the model parameters and improves model accuracy based on new patient data. The model perspective was a combination of particle filtering and parameter estimation. To demonstrate the feasibility and further evaluate the performance of our approach, we performed an empirical analysis experiment. The study showed that our method achieved an overall accuracy of 92% and a recall of 71% for deceased patients. Compared with traditional machine learning models, the accuracy of the model estimated by particle filter parameters has been improved by 2%, and the recall rate for dead patients has been improved by 11%. Additionally, this study outcome shows that this method can better utilize subsequent patients' characteristic data, be more relevant to different patients, and help achieve precision medicine.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/pathology , Prognosis , Lung Neoplasms/diagnosis , Lung Neoplasms/pathology , Risk Assessment , Algorithms
7.
BMC Med Inform Decis Mak ; 23(1): 251, 2023 11 06.
Article in English | MEDLINE | ID: mdl-37932733

ABSTRACT

BACKGROUND: In the healthcare domain today, despite the substantial adoption of electronic health information systems, a significant proportion of medical reports still exist in paper-based formats. As a result, there is a significant demand for the digitization of information from these paper-based reports. However, the digitization of paper-based laboratory reports into a structured data format can be challenging due to their non-standard layouts, which includes various data types such as text, numeric values, reference ranges, and units. Therefore, it is crucial to develop a highly scalable and lightweight technique that can effectively identify and extract information from laboratory test reports and convert them into a structured data format for downstream tasks. METHODS: We developed an end-to-end Natural Language Processing (NLP)-based pipeline for extracting information from paper-based laboratory test reports. Our pipeline consists of two main modules: an optical character recognition (OCR) module and an information extraction (IE) module. The OCR module is applied to locate and identify text from scanned laboratory test reports using state-of-the-art OCR algorithms. The IE module is then used to extract meaningful information from the OCR results to form digitalized tables of the test reports. The IE module consists of five sub-modules, which are time detection, headline position, line normalization, Named Entity Recognition (NER) with a Conditional Random Fields (CRF)-based method, and step detection for multi-column. Finally, we evaluated the performance of the proposed pipeline on 153 laboratory test reports collected from Peking University First Hospital (PKU1). RESULTS: In the OCR module, we evaluate the accuracy of text detection and recognition results at three different levels and achieved an averaged accuracy of 0.93. In the IE module, we extracted four laboratory test entities, including test item name, test result, test unit, and reference value range. The overall F1 score is 0.86 on the 153 laboratory test reports collected from PKU1. With a single CPU, the average inference time of each report is only 0.78 s. CONCLUSION: In this study, we developed a practical lightweight pipeline to digitalize and extract information from paper-based laboratory test reports in diverse types and with different layouts that can be adopted in real clinical environments with the lowest possible computing resources requirements. The high evaluation performance on the real-world hospital dataset validated the feasibility of the proposed pipeline.


Subject(s)
Algorithms , Natural Language Processing , Humans , Information Storage and Retrieval , Hospitals, University , Electronic Health Records
8.
Org Lett ; 25(28): 5185-5190, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37439552

ABSTRACT

Cp*Rh(III)-catalyzed nitro-directed C-H alkylation/alkenylation of nitroarenes has been reported for the first time. This protocol is associated with the features of high efficiency, broad substrate scope, and good functional group compatibility. Additionally, gram-scale experiments and synthetic applications proved the practicability of the method. Moreover, preliminary mechanistic investigations consistently revealed C-H bond cleavage as the rate-limiting step.

9.
Org Lett ; 25(28): 5179-5184, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37415264

ABSTRACT

Rh (III)-catalyzed dienylation and cyclopropylation of 1,2,3-benzotriazinones with alkylidenecyclopropanes (ACPs) has been achieved. Different from the previous reports of 1,2,3-benzotriazinones, the triazinone ring remained intact in this C-H bond functionlization reaction. Also, the denitrogenative cyclopropylation could also be realized by changing the reaction temperature. This protocol is featured with high E selectivity, wide substrate scope, and divergent structures of products.

10.
Org Lett ; 25(23): 4286-4291, 2023 Jun 16.
Article in English | MEDLINE | ID: mdl-37265108

ABSTRACT

Two categories of tetrasubstituted phenols were prepared via the cycloaddition reaction of vinyl sulfoxonnium ylides with cyclopropenones in a switchable manner. Copper carbenoid was proposed as the active intermediate in the process of 2,3,4,5-tetrasubstituted phenols formation, while 2,3,5,6-tetrasubstituted phenols were generated via the direct [3 + 3] annulation of vinyl sulfoxonnium ylides with cyclopropenones under metal-free conditions. Further synthetic applications were also demonstrated.


Subject(s)
Copper , Metals , Catalysis , Cycloaddition Reaction
11.
Biomedicines ; 11(6)2023 Jun 03.
Article in English | MEDLINE | ID: mdl-37371723

ABSTRACT

Prostate cancer (PCa) is a critical global public health issue with its incidence on the rise. Radiation therapy holds a primary role in PCa treatment; however, radiation resistance has become increasingly challenging as we uncover more about PCa's pathogenesis. Our review aims to investigate the multifaceted mechanisms underlying radiation therapy resistance in PCa. Specifically, we will examine how various factors, such as cell cycle regulation, DNA damage repair, hypoxic conditions, oxidative stress, testosterone levels, epithelial-mesenchymal transition, and tumor stem cells, contribute to radiation therapy resistance. By exploring these mechanisms, we hope to offer new insights and directions towards overcoming the challenges of radiation therapy resistance in PCa. This can also provide a theoretical basis for the clinical application of novel ultra-high-dose-rate (FLASH) radiotherapy in the era of PCa.

12.
J Org Chem ; 88(9): 5512-5519, 2023 May 05.
Article in English | MEDLINE | ID: mdl-37011236

ABSTRACT

The indole-substituted trifluoromethyl sulfonium ylide has been developed via Cp*Rh(III)-catalyzed diazo-carbenoid addition to trifluoromethylthioether and is the first example of an Rh(III)-catalyzed diazo-carbenoid addition reaction with trifluoromethylthioether. Several kinds of indole-substituted trifluoromethyl sulfonium ylide were constructed under mild reaction conditions. The reported method exhibited high functional group compatibility and broad substrate scope. In addition, the protocol was found to be complementary to the method disclosed by a Rh(II) catalyst.

13.
J Org Chem ; 88(6): 3499-3508, 2023 Mar 17.
Article in English | MEDLINE | ID: mdl-36891880

ABSTRACT

Rh(III)-catalyzed C-H/N-H annulation and C-H allylation of phenylindazolones have been realized by employing 5-methylene-1,3-dioxan-2-one and 4-vinyl-1,3-dioxolan-2-one as scalable cross-coupling partners, delivering functionalized indazolone fused heterocycles and branched and linear allyl indazolones respectively in moderate to high yield. These divergent synthesis protocols showcase mild conditions, broad substrate scope, and high functional-group compatibility. In addition, scale-up synthesis and preliminary mechanistic exploratory were also accomplished.

14.
Org Biomol Chem ; 20(25): 5055-5059, 2022 06 29.
Article in English | MEDLINE | ID: mdl-35695281

ABSTRACT

Herein, we report a Rh(III)-catalyzed C4-selective activation of indoles by using iodonium ylides as carbene precursors. This protocol proceeded under redox neutral reaction conditions and provided important coupling products with good tolerance of functional groups and high yields. In addition, one-pot synthesis and scale-up and mechanistic studies were also conducted.


Subject(s)
Rhodium , Catalysis , Indoles , Oxidation-Reduction
15.
Materials (Basel) ; 15(12)2022 Jun 11.
Article in English | MEDLINE | ID: mdl-35744213

ABSTRACT

In this paper, a polycrystalline diamond was synthesized by the direct detonation method using graphite as the carbon source. By comparing the numbers of the obtained diamond particles and the original graphite particles, it was found that when the graphite phase transformed into the polycrystalline diamond during the detonation process, a single graphite particle would form multiple diamond nuclei, and the nuclei would grow simultaneously to form polycrystals. Accordingly, a validation experiment was designed, which added different ratios of inert additives while keeping the ratio of graphite to hexogen (RDX) unchanged. It was found that increasing the ratio of inert additives within a certain range could increase the grain size of a polycrystalline diamond, which is consistent with the obtained polycrystalline mechanism.

16.
Org Biomol Chem ; 20(3): 565-569, 2022 01 19.
Article in English | MEDLINE | ID: mdl-34985096

ABSTRACT

A thioether directed acyloxylation of arenes has been realized via Cp*Rh(III)-catalyzed C-H activation and subsequent coupling with carboxylic acids. This new method showed high functional group compatibility and broad substrate scope. Primary mechanistic studies have been conducted and a tentative reaction mechanism was proposed. It represents the first example of a thioether-directed Cp*Rh(III)-catalyzed C(sp2)-H acyloxylation reaction.

17.
J Asian Nat Prod Res ; 24(2): 153-162, 2022 Feb.
Article in English | MEDLINE | ID: mdl-33583288

ABSTRACT

Two novel acylated steroidal sapogenins, 3ß-acetoxy-1α, 2α, 4ß, 5α, 7α-pentahydroxy-spirost-25(27)-en-6-one (1) and (25S)-3α-acetoxy-1α, 2ß, 4α, 5α, 7α-pentahydroxyspirostan-6-one (2), together with two known steroidal sapogenins (3 and 4), were isolated from Rohdea chinensis rhizomes. Their structures were elucidated by nuclear magnetic resonance (NMR) and mass spectrometry (MS) data. In addition, the antifungal activities of the isolated compounds against Penicillium digitatum and Rhizopus stolonifera were evaluated. Compound 2 significantly inhibited R. stolonifera growth, which was comparable to the positive control (sodium benzoate and carbendazim). Compound 4 showed the highest potency to inhibit P. digitatum growth compared to other compounds.


Subject(s)
Sapogenins , Saponins , Antifungal Agents/pharmacology , Molecular Structure , Rhizome
18.
Front Bioeng Biotechnol ; 9: 783003, 2021.
Article in English | MEDLINE | ID: mdl-34900972

ABSTRACT

The active behaviors of pedestrians, such as avoidance motions, affect the resultant injury risk in vehicle-pedestrian collisions. However, the biomechanical features of these behaviors remain unquantified, leading to a gap in the development of biofidelic research tools and tailored protection for pedestrians in real-world traffic scenarios. In this study, we prompted subjects ("pedestrians") to exhibit natural avoidance behaviors in well-controlled near-real traffic conflict scenarios using a previously developed virtual reality (VR)-based experimental platform. We quantified the pedestrian-vehicle interaction processes in the pre-crash phase and extracted the pedestrian postures immediately before collision with the vehicle; these were termed the "pre-crash postures." We recorded the kinetic and kinematic features of the pedestrian avoidance responses-including the relative locations of the vehicle and pedestrian, pedestrian movement velocity and acceleration, pedestrian posture parameters (joint positions and angles), and pedestrian muscle activation levels-using a motion capture system and physiological signal system. The velocities in the avoidance behaviors were significantly different from those in a normal gait (p < 0.01). Based on the extracted natural reaction features of the pedestrians, this study provides data to support the analysis of pedestrian injury risk, development of biofidelic human body models (HBM), and design of advanced on-vehicle active safety systems.

19.
J Org Chem ; 86(23): 17063-17070, 2021 12 03.
Article in English | MEDLINE | ID: mdl-34797073

ABSTRACT

A tandem rhodium(III)-catalyzed system was established to access 3,4-dihydroisoquinolin-1(2H)-one by coupling of N-methoxy-3-methylbenzamide with 2-methylidenetrimethylene carbonate. This one-pot synthesis protocol processed smoothly under mild reaction conditions. Moreover, a total of 28 examples, broad substrate scope, and high functional-group compatibility were observed. Preliminary mechanism studies were also conducted and demonstrated that the rhodium(III) catalyst played a vital role in the C-H-allylation and N-alkylation cyclization process.


Subject(s)
Rhodium , Alkylation , Carbonates , Catalysis , Cyclization
20.
Org Biomol Chem ; 19(39): 8487-8491, 2021 10 14.
Article in English | MEDLINE | ID: mdl-34545904

ABSTRACT

An efficient and practical approach for the synthesis of medicinally important acridones was developed from anthranils and commercially available arylboronic acids by a tandem copper(I)-catalyzed electrophilic amination/Ag(I)-mediated oxidative annulation strategy. This new and straightforward protocol displayed a broad substrate scope (25 examples) and high functional group tolerance. What's more, a possible mechanistic proposal was also presented.


Subject(s)
Copper
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