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Natural products with the 3,6‐diene‐2,5‐diketopiperazine core are widely distributed in nature; however, the biosynthetic mechanism of 3,6‐diene‐2,5‐diketopiperazine in fungi remains to be further elucidated. Through heterologous expression and biochemical investigation of an FeII/2‐oxoglutarate‐dependent oxidase (AspE) and a heme‐dependent P450 enzyme (AspF), we report that AspE, AspF and subsequent dehydration account for the formation of the 3,6‐diene‐2,5‐diketopiperazine substructure of brevianamide K from Aspergillus sp. SK‐28, a symbiotic fungus of mangrove plant Kandelia candel. More interestingly, in‐depth investigation of the enzymatic mechanism showed that AspE promotes hydroxylation of brevianamide Q with unprecedented stereoinversion through hydrogen atom abstraction and water nucleophilic attack from the opposite face of the resultant iminium cation intermediate. [ABSTRACT FROM AUTHOR]

Natural products with the 3,6‐diene‐2,5‐diketopiperazine core are widely distributed in nature; however, the biosynthetic mechanism of 3,6‐diene‐2,5‐diketopiperazine in fungi remains to be further elucidated. Through heterologous expression and biochemical investigation of an FeII/2‐oxoglutarate‐dependent oxidase (AspE) and a heme‐dependent P450 enzyme (AspF), we report that AspE, AspF and subsequent dehydration account for the formation of the 3,6‐diene‐2,5‐diketopiperazine substructure of brevianamide K from Aspergillus sp. SK‐28, a symbiotic fungus of mangrove plant Kandelia candel. More interestingly, in‐depth investigation of the enzymatic mechanism showed that AspE promotes hydroxylation of brevianamide Q with unprecedented stereoinversion through hydrogen atom abstraction and water nucleophilic attack from the opposite face of the resultant iminium cation intermediate. [ABSTRACT FROM AUTHOR]

Domain adaptation is the ability to improve the learning efficiency of the target domain by using the prior knowledge of the source domain. When applied to new tasks in the target domain, the performance of domain adaptation trained in the source domain declines sharply. The purpose is to realize a new retrieval task in the target domain using only a small number of labelled data samples, with the aid of the prior knowledge learned in the source domain. This paper focuses on semi-supervised domain adaptation in remote sensing image retrieval. The contributions of this paper are threefold. First, we construct Gabor-based CNNs to facilitate the networks to effectively capture the texture information of images. Second, we propose a cross-domain knowledge transfer strategy based on dual Gabor neural network learning. Third, we propose an unsupervised random feature mapping method based on probability distance. A large number of experiments have been conducted on UCM, WHU-RS, RSSCN7, AID, and PatternNet datasets. The results show that this method greatly improves the retrieval accuracy on the target domain and obtains state-of-the-art retrieval accuracy. The source code is available at . [ABSTRACT FROM AUTHOR]

Southern China and Southeast Asia witnessed some of their most significant economic and social changes relevant to human land use during the Late Holocene, including the intensification and spread of rice agriculture. Despite rice growth being associated with a number of earth systems impacts, how these changes transformed tropical vegetation in this region of immense endemic biodiversity remains poorly understood. Here, we compile a pollen dataset incorporating ∼150,000 identifications and 233 pollen taxa to examine past changes in floral biodiversity, together with a compilation of records of forest decline across the region using 14 pollen records spanning lowland to mountain sites. Our results demonstrate that the rise of intensive rice agriculture from approximately 2,000 y ago led not only to extensive deforestation but also to remarkable changes of vegetation composition and a reduction in arboreal diversity. Focusing specifically on the Tertiary relic tree species, the freshwater wetland conifer Glyptostrobus (Glyptostrobus pensilis), we demonstrate how key species that had survived changing environmental conditions across millions of years shrank in the face of paddy rice farming and human disturbance. [ABSTRACT FROM AUTHOR]

Circular RNAs, as hopeful diagnosis markers and therapeutic molecules, have been studied, probed and applied into several diseases, such as cardiovascular diseases, systemic lupus erythematosus, leukemia, pulmonary tuberculosis, and cancer especially. Recently, mounting evidence has supported that circRNAs play a key role in the tumorigenesis, progress, invasion and metastasis in lung cancer. Its special structure—3′–5′ covalent loop—allow it to execute several special functions in both normal eukaryotic cells and cancer cells. Our review summaries the latest studies on characteristics and biogenesis of circRNAs, and highlight the regulatory functions about miRNA sponge of lung-cancer-related circRNAs. In addition, the interaction of the circRNA-miRNA-mRNA regulatory network will also be elaborated in detail in this review. Therefore, this review can provide a new idea or strategy for further development and application in clinical setting in terms of early-diagnosis and better treatment. [ABSTRACT FROM AUTHOR]

In this study, a theoretical model of one dimensional fracture grouting in soil is proposed based on fluid mechanics and force analysis during grout fracturing process. Solutions for grout pressure, and the length and width of the fracture are obtained, and the influence of the yield strength on the fracturing behavior is analyzed. Results show that, the grouting distance decreases and the fracture height increases as the yield strength of grout increases. A laboratory test was carried out in this study to validate the proposed theoretical model. The dimension of the solidified grout was measured after excavation. For higher yield strength, the grout front has a blunt shape, which means the pushing effect plays a more important role than the fracturing effect and the fracturing process was controlled by different mechanisms for different yield strength during the experiment. Comparison between the theoretical and the experimental results shows that the proposed model can effectively describe the fracture grouting process. [ABSTRACT FROM AUTHOR]

The Amur Basin, on the border of Russia and China, has accumulated substantial quantities of peat that have allowed the reconstruction of past vegetation and environments, especially during the Holocene. In this paper, a detailed pollen record from the Basin has been constructed for the last 3800 years and interpreted with the assistance of 40 surface pollen samples taken from vegetation types representative of a broader region. In addition, fossil microcharcoal counts were undertaken to explore variation in fire frequency and the role of fire in peat development and landscape disturbance. The record can be divided into four periods. (1) A period of deciduous broadleaved forest dominated by Betula and Quercus accompanied by thriving sedge-dominated wetlands indicating relatively warm and wet conditions between about 3800 and 2000 cal BP. (2) Coniferous and broad-leaved mixed forest domination between about 2000 and 680 cal BP indicating a shift to a cooler climate. (3) Betula-dominant deciduous forest, reduced sedge-dominated wetlands and increased burning between about 680 and 250 cal BP indicating further drying and cooling during the Little Ice Age. (4) Secondary pine forest combined with a large increase in fire activity as well as a further reduction in the swamp environment signaling substantial human impact in the last 250 years. [ABSTRACT FROM AUTHOR]

Let the construction achievement of special laboratory in local colleges and universities benefit students. We use campus network curriculum resources, sharing teaching and practice platform to open public selective courses for engineering students in our university. The teaching reform for public courses begins with course contents, ideas, experiments environment and so on, and pays attention to the teaching team cultivation. The teaching material construction emphasizes on the level of theoretic teaching. Constructing teaching video results in the active learning of students. Therefore, the teaching quality is improved and the practice activities of students are enhanced. We provide the electronic design contest and innovation activities to students, and let the students acquire the ability of practice and innovation, then increase the ability of exploration of scientific phenomena. The scientific research would be more clear for our students. [ABSTRACT FROM AUTHOR]

We report on a new class of P-O monophosphite ligands (designated 8a-k) with a double six-membered-ring backbone onto which are attached additional groups and on applications of their Rh complexes in the hydrogenation of enamides, α-dehydroamino acid esters, dimethyl itaconate, and β-(acylamino)acrylates. Our results demonstrate that the Rh complexes with ligands 8a-k exhibit high enantioselectivity and reactivity in asymmetric hydrogenation reactions. An ee value of up to 98.0% was obtained for the hydrogenation of α-dehydroamino acid esters, and the ee values were all over 99% for the other three types of substrate, with a turnover number of up to 5000. [ABSTRACT FROM AUTHOR]

In recent years, the amount of remote sensing imagery data has increased exponentially. The ability to quickly and effectively find the required images from massive remote sensing archives is the key to the organization, management, and sharing of remote sensing image information. This paper proposes a high-resolution remote sensing image retrieval method with Gabor-CA-ResNet and a split-based deep feature transform network. The main contributions include two points. (1) For the complex texture, diverse scales, and special viewing angles of remote sensing images, A Gabor-CA-ResNet network taking ResNet as the backbone network is proposed by using Gabor to represent the spatial-frequency structure of images, channel attention (CA) mechanism to obtain stronger representative and discriminative deep features. (2) A split-based deep feature transform network is designed to divide the features extracted by the Gabor-CA-ResNet network into several segments and transform them separately for reducing the dimensionality and the storage space of deep features significantly. The experimental results on UCM, WHU-RS, RSSCN7, and AID datasets show that, compared with the state-of-the-art methods, our method can obtain competitive performance, especially for remote sensing images with rare targets and complex textures. [ABSTRACT FROM AUTHOR]

Recently, there have been rapid advances in high-resolution remote sensing image retrieval, which plays an important role in remote sensing data management and utilization. For content-based remote sensing image retrieval, low-dimensional, representative and discriminative features are essential to ensure good retrieval accuracy and speed. Dimensionality reduction is one of the important solutions to improve the quality of features in image retrieval, in which LargeVis is an effective algorithm specifically designed for Big Data visualization. Here, an extended LargeVis (E-LargeVis) dimensionality reduction method for high-resolution remote sensing image retrieval is proposed. This can realize the dimensionality reduction of single high-dimensional data by modeling the implicit mapping relationship between LargeVis high-dimensional data and low-dimensional data with support vector regression. An effective high-resolution remote sensing image retrieval method is proposed to obtain stronger representative and discriminative deep features. First, the fully connected layer features are extracted using a channel attention-based ResNet50 as a backbone network. Then, E-LargeVis is used to reduce the dimensionality of the fully connected features to obtain a low-dimensional discriminative representation. Finally, L2 distance is computed for similarity measurement to realize the retrieval of high-resolution remote sensing images. The experimental results on four high-resolution remote sensing image datasets, including UCM, RS19, RSSCN7, and AID, show that for various convolutional neural network architectures, the proposed E-LargeVis can effectively improve retrieval performance, far exceeding other dimensionality reduction methods. [ABSTRACT FROM AUTHOR]

Rice agriculture is the foundation of Asian civilizations south of the Yangtze River. Although rice history is well documented for its lower Yangtze homeland area, the early southward expansion of paddy rice farming is poorly known. Our study investigates this process using a compilation of paleoenvironmental proxies from coastal sediment cores from southeast China to Thailand and Island Southeast Asia. We propose that a shortage of land suitable for paddy fields, caused by marine transgression, constrained rice agriculture during the mid-Holocene. Rapid expansion of coastal plains, particularly in deltaic basins, over the past three millennia has coincided with increases in land suitable for rice cultivation. Our study also helps explain the past population movements of rice farmers. [ABSTRACT FROM AUTHOR]

This study has reconstructed the Holocene environmental history of central Tibetan Plateau, a transitional area between monsoon-dominated Asia and Westerlies-dominated Asia, to examine the interplay between the two circulation systems and effects of other potential mechanisms on the temporal variability of Holocene climatic conditions in the study area. Specifically, this study has produced a twin record of palaeo-hydrology and palaeotemperature from an alpine wetland sediment sequence using two sets of lipid-based biomarker indices: n-alkanes and branched glycerol dialkyl glycerol tetraethers (bGDGTs). The results show that (1) the Asian summer monsoon has supplied moisture that helped initiate the wetland habitat around 8000 cal. yr BP, about 2000 years later than locations along the southeastern edge of the plateau; (2) a significant decline in moisture supply is evident since the Medieval Warm period; (3) the Westerlies have transmitted variability of the North Atlantic climate to the study area, resulting in periodic increases in evaporation and causing short-term expansion or contraction of the wetland and (4) the palaeo-air temperature change follows closely that of global sea level and sea surface temperature, implying a link to global ice volume change throughout the Holocene. This study concludes that the Holocene climate history of central Tibetan Plateau is a result of monsoonal moisture supply interacted with the Westerlies variability, while the palaeo-temperature has followed changes in global ice volume during the present warm interglacial. [ABSTRACT FROM AUTHOR]

The uplift of the Tibet Plateau (TP) during the Miocene is crucial to understanding the evolution of Asian monsoon regimes and alpine biodiversity. However, the northern Tibet Plateau (NTP) remains poorly investigated. We use pollen records of montane conifers (Tsuga, Podocarpus, Abies, and Picea) as a new paleoaltimetry to construct two parallel midrange paleoelevation sequences in the NTP at 1332 ± 189 m and 433 ± 189 m, respectively, during the Middle Miocene [~15 million years ago (Ma)]. Both midranges increased rapidly to 3685 ± 87 m in the Late Miocene (~11 Ma) in the east, and to 3589 ± 62 m at ~7 Ma in the west. Our estimated rises in the east and west parts of the NTP during 15 to 7 Ma, together with data from other TP regions, indicate that during the Late Miocene the entire plateau may have reached a high elevation close to that of today, with consequent impacts on atmospheric precipitation and alpine biodiversity. [ABSTRACT FROM AUTHOR]

Na-doped Ni-rich LiNi0.5Co0.2Mn0.3O2 cathode material, Li0.97Na0.03Ni0.5Co0.2Mn0.3O2, is synthesized by a hydroxide co-precipitation route. The structural characterization reveals that the substitution of Na for Li results in a more ordered α-NaFeO2 structure, enlarges Li layer spacing, and reduces the degree of cation mixing. The Li0.97Na0.03Ni0.5Co0.2Mn0.3O2 material has a high tap density of 2.17 g cm-3 that meets the commercial requirement in lithium ion batteries (LIBs). The galvanostatic charge/discharge results show that the electrochemical performance of the Li0.97Na0.03Ni0.5Co0.2Mn0.3O2 is significantly improved. At 0.2, 1, 10, 30 and 50 C, the specific capacities of the Li0.97Na0.03Ni0.5Co0.2Mn0.3O2 are 228.43, 163.12, 121.43, 95.56 and 60.09 mA h g-1, respectively, which are superior to those of the undoped LiNi0.5Co0.2Mn0.3O2 due to the enlargement of Li layer spacing, the decreased degree of cation mixing, and the rapid diffusion of Li-ion in the bulk lattice after the substitution of Na for Li. Therefore, the Na-doped Ni-rich LiNi0.5Co0.2Mn0.3O2 material is a promising cathode candidate for the next generation of LIBs. [ABSTRACT FROM AUTHOR]

Here we describe the LegacyClimate 1.0, a dataset of the reconstruction of mean July temperature (TJuly), mean annual temperature (Tann), and annual precipitation (Pann) from 2594 fossil pollen records from the Northern Hemisphere spanning the entire Holocene with some records reaching back to the Last Glacial. Two reconstruction methods, the Modern Analogue Technique (MAT) and Weighted-Averaging Partial-Least Squares regression (WA-PLS) reveal similar results regarding spatial and temporal patterns. To reduce the impact of precipitation on temperature reconstruction and vice versa, we also provide reconstructions using tailored modern pollen data limiting the range of the corresponding other climate variables. We assess the reliability of the reconstructions using information from the spatial distributions of the root-mean squared error of prediction and reconstruction significance tests. The dataset is beneficial for climate proxy synthesis studies and to evaluate the output of climate models and thus help to improve the models themselves. We provide our compilation of reconstructed TJuly, Tann, and Pann as open-access datasets at PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.930512; Herzschuh et al., 2021). R code for the reconstructions is provided at Zenodo (https://doi.org/10.5281/zenodo.5910989; Herzschuh et al., 2022), including harmonized open-access modern and fossil datasets used for the reconstructions, so that customized reconstructions can be easily established. [ABSTRACT FROM AUTHOR]

Interleukin (IL)‐37 has been described as a negative regulator of immune responses and is critical for asthma pathogenesis, but the mechanisms behind the protective role of IL‐37 against allergic asthma are less well understood. We show here that IL‐37 administered intranasally inhibited house dust mite (HDM)‐induced chronic airway eosinophilic inflammation, goblet cell hyperplasia, peribronchial collagen deposition and airway hyperresponsiveness (AHR) to methacholine. In contrast to a weakened Th2 response in the lung that was characterized by the downregulation of Th2‐associated cytokines and chemokines in IL‐37‐treated mice, IL‐37 has no effect on relevant markers of systemic Th2 immune including serum immunoglobulins expression and in vitro production of Th2‐associated cytokines by splenocytes on HDM recall. We demonstrated that the production of thymic stromal lymphopoietin (TSLP) in the lung tissue was associated with IL‐37. Importantly, compared with IL‐37 alone, TSLP coadministration with IL‐37 restored HDM‐induced airway inflammation and structural alterations, increased AHR to methacholine and promoted Th2‐associated cytokine production. We further found that IL‐37 inhibited the induction of TSLP expression by the main antigen of house dust mite, Der p1, by suppressing NF‐κB and extracellular signal regulated kinase 1/2 (ERK1/2) activation in human bronchial epithelial (16‐HBE) cells in vitro. These data highlight the importance of TSLP in IL‐37‐mediated protective role in asthma. IL‐37 might represent a useful innovative and alternative therapy to control TSLP production in the airway. [ABSTRACT FROM AUTHOR]

Human influence on vegetation is a potential confounding factor in pollen-based quantitative climate reconstructions. Here, we examine this issue in China, a region with intensive and long-lasting human influence. We employ modern datasets for human influence index (HII), climate and pollen over continental China to develop quantitative calibration models for HII and two key climate variables (annual precipitation, PANN; annual mean temperature, TANN). We assess the effect of HII on modern pollen assemblages and individual pollen taxa by comparison with climate variables by using constrained ordination methods and boosted regression trees and apply the calibration models to a pollen record spanning the last 6200 years from Lake Tianchi in central China. The results show that HII has smaller influence on the modern pollen data than PANN and TANN, except for in east-central China where the relationship between pollen data and HII is both statistically and ecologically significant. The reconstructed HII from Lake Tianchi remains relatively stable at 6200-2900 cal. yr BP, rises gradually at 2900-1100 cal. yr BP, and increases abruptly 1100 years ago. These HII trends are roughly concordant with Holocene charcoal and historical population records. The climate reconstructions change in tune with the HII, with an abrupt decline of PANN and a rise of TANN after 1100 cal. yr BP. Other palaeoclimatic data contradict the reconstructed patterns of PANN and TANN during the last millennium, suggesting that the climate reconstructions over the last 11 centuries are seriously biased due to the marked increase of human influence. Such a bias likely exists in other pollen-based climate reconstructions from other regions with strong and long-lasting human influence on vegetation. [ABSTRACT FROM AUTHOR]

A new Cu-catalyzed asymmetric [3 + 3] cycloaddition of propargyl esters with cyclic enamines is reported. With a combmatiori of Cu(OAc)2∙H2O and a chiral tridentate ferrocenyl-P,N,N ligand as the catalyst, perfect endo selectivities (endo/exo > 98/2) and excellent enantioselectivities (up to 98% ee) for endo cycloadducts were achieved under mild conditions. This method provides a simple and efficient approach for the synthesis of optically active bicyclo[n.3.1] frameworks. [ABSTRACT FROM AUTHOR]

A new family of chiral ferrocenyl P,S-ligands has been developed and successfully applied in a highly endo-selective catalytic asymmetric cycloaddition of azomethine ylides with various enones, including cyclic and acyclic α-enones. For cyclic α-enones, a [Cu(CH3CN)4]ClO4/(Rc,SFc)-2fcomplex catalyzed the cycloaddition to give the sole endo-cycloadducts in perfect enantioselectivities (normally 99% ee), while an AgOAc/(Rc,SFc)-2fcatalytic system exhibited good endo/exoselectivities (endo/exo= 91/9 to 96/4) and high enantiocontrol (up to 98% ee) for acyclic α-enones. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of chiral alkylphosphonates bearing a β-stereogenic center, based on the Rh-catalyzed asymmetric hydrogenation of corresponding β-substituted β,γ-unsaturated phosphonates with a ferrocenebased monophosphoramidite ligand under the mild hydrogenation conditions, was developed, in which an ee value of up to 98% was obtained. [ABSTRACT FROM AUTHOR]

A new class of chiral ferrocenyl diphosphine ligands with an imidazole ring, (Rc,SFc)-ImiFerroPhos, has been prepared from acylferrocenes through a five-step transformation and successfully applied in the Rh-catalyzed asymmetric hydrogenation of various 3-aryl-substituted 2-phosphonomethylpropenoates, in which a series of chiral 3-phosphono-2-arylmethylpropanoic acid derivatives were achieved in ee values of up to 98%. [ABSTRACT FROM AUTHOR]

A new class of unsymmetrical hybrid phosphine-aminophosphine ligands has been prepared from commercially available, inexpensive (S)-1-phenylethylamine through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and displayed good enantioselectivities in the Rh-catalyzed asymmetric hydrogenation of various dimethyl α-benzoyloxyethenephosphonates bearing β-aryl, β-alkyl, and β-alkoxy substituents and N-benzyloxycarbonyl α-enamido phosphonates, in which up to 97% ee was obtained. A side-by-side comparison study disclosed that these new phosphine-aminophosphine ligands showed better enantioselectivity than BoPhoz ligands. [ABSTRACT FROM AUTHOR]

A series of chiral -aryl--amino acid ester derivatives were synthesized in high enantioselectivities (93−97% ee) via the Rh-catalyzed asymmetric hydrogenation of -phthalimido-,-unsaturated carboxylic acid esters using highly modular chiral BoPhoz-type phosphine−aminophosphine ligands. The method has been applied successfully to the synthesis of several chiral pharmaceuticals including (R)-baclofen and (R)-rolipram with high enantioselectivities. [ABSTRACT FROM AUTHOR]

A new family of unsymmetrical ferrocenylethylamine-derived monophosphoramidites were synthesized and successfully applied in the Rh-catalyzed enantioselective hydrogenation of a range of enamides and α-dehydroamino acid esters, and ee values of up to 99.5% were obtained for both types of substrate. These results suggest that unsymmetrical amine-derived monophosphoramidites can also exhibit excellent enantioselectivity for a broad range of substrates, comparable to or higher than those of the most efficient symmetrical amine-derived monophosphoramidites reported thus far. [ABSTRACT FROM AUTHOR]

A new series of fine-tunable phosphite-pyridine (P,N) ligands derived from (S)-2-amino-2'-hydroxy-6,6'-dimethyl-1,1'-biphenyl and (S)-2-amino-2'-hydroxy-4,4',6,6'tetramethyl-1,1'-biphenyl was employed in Cu(I)-catalyzed conjugate addition of diethylzinc to acyclic enones. Excellent enantioselectivities (up to 98% ee) and highly catalytic activities were achieved for a variety of acyclic enones. [ABSTRACT FROM AUTHOR]

A new type of phosphite-pyridine (P,N) ligand derived from (S)-NOBIN and (S)-BINOL was employed in Cu(I)-catalyzed conjugate addition of diethylzinc to chalcones. The new P,N ligands were highly efficient in the copper-catalyzed enantioselective 1,4-conjugate additions of diethylzinc to acyclic enones, and up to 97% ee was achieved. [ABSTRACT FROM AUTHOR]

A series of chiral 3-aryl-4-phosphonobutyric acid esters were synthesized in high enantioselectivities (93-98% ee) via the Rh-catalyzed asymmetric hydrogenation of the corresponding 3-aryl-4-phosphonobutenoates using a P-stereogenic BoPhoz-type phosphine-aminophosphine ligand. The methodology has been successfully applied to the asymmetric synthesis of a potential GABAB antagonist, (R)-phaclofen, in high enantioselectivity. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of optically active 1-aryl or 1-alkyl substituted ethyiphosphonates, based on the first Rh- catalyzed asymmetric hydrogenation of corresponding α,β-unsaturated precursors with a P-stereogenic BoPhoz-type ligand under the mild condition, was developed, in which a wide range of 1-aryl or 1-alkyl substituted ethyiphosphonates were achieved in up to 98% ee. [ABSTRACT FROM AUTHOR]

A series of chiral β-aryl-substituted γ-amino butyric acid derivatives were synthesized in good enantioselectivities via the Cu-catalyzed asymmetric conjugate reduction of γ-phthalimido-α,β-unsaturated carboxylic acid esters using Cu(OAc)2·H2O as a catalyst precursor, (S)-BINAP as a ligand, PMHS as a hydride source, and t-BuOH as an additive. The methodology has been applied successfully to the enantioselective synthesis of a chiral pharmaceutical, (R)-baclofen. [ABSTRACT FROM AUTHOR]

A series of BoPhoz-type ligands were successfully applied in the rhodium-catalyzed asymmetric hydrogenation of a number of β-substituted or unsubstituted α-(phthalimidomethyl)acrylates, affording good to excellent enantioselectivities. The results suggested that the presence of an N-H proton in the BoPhoz backbone could significantly improve the enantioselectivity, and ligand (Sc,Rp)-1d, bearing two CF3-groups in the 3,5-position of the phenyl ring of aminophosphino moiety, showed the highest enantioselectivity. [ABSTRACT FROM AUTHOR]