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Li D, Zhou Z, Qing D, He Y, Wu T, Miao M, Wang J, Weng X, Ferber J, Herrinton L, Zhu Q, Gao E, Checkoway H, Yuan W. Occupational exposure to bisphenol-A (BPA) and the risk of Self-Reported Male Sexual Dysfunction. Hum Reprod 2009; 25:519-27. [DOI: 10.1093/humrep/dep381] [Citation(s) in RCA: 204] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Li DK, Zhou Z, Miao M, He Y, Qing D, Wu T, Wang J, Weng X, Ferber J, Herrinton LJ, Zhu Q, Gao E, Yuan W. Relationship Between Urine Bisphenol-A Level and Declining Male Sexual Function. ACTA ACUST UNITED AC 2010; 31:500-6. [DOI: 10.2164/jandrol.110.010413] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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89 |
3
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Xu J, Yuan S, Miao M. N-Heterocyclic Carbene Catalyzed [4 + 2] Annulation Reactions with in Situ Generated Heterocyclic ortho-Quinodimethanes. Org Lett 2016; 18:3822-5. [DOI: 10.1021/acs.orglett.6b01831] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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77 |
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Lim BS, Willer MW, Miao M, Holm RH. Monodithiolene molybdenum(V, VI) complexes: a structural analogue of the oxidized active site of the sulfite oxidase enzyme family. J Am Chem Soc 2001; 123:8343-9. [PMID: 11516283 DOI: 10.1021/ja010786g] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The active sites of the xanthine oxidase and sulfite oxidase enzyme families contain one pterin-dithiolene cofactor ligand bound to a molybdenum atom. Consequently, monodithiolene molybdenum complexes have been sought by exploratory synthesis for structural and reactivity studies. Reaction of [MoO(S(2)C(2)Me(2))(2)](1-) or [MoO(bdt)(2)](1-) with PhSeCl results in removal of one dithiolate ligand and formation of [MoOCl(2)(S(2)C(2)Me(2))](1-) (1) or [MoOCl(2)(bdt)](1-) (2), which undergoes ligand substitution reactions to form other monodithiolene complexes [MoO(2-AdS)(2)(S(2)C(2)Me(2))](1-) (3), [MoO(SR)(2)(bdt)](1-) (R = 2-Ad (4), 2,4,6-Pr(i)(3)C(6)H(2) (5)), and [MoOCl(SC(6)H(2)-2,4,6-Pr(i)(3))(bdt)](1-) (6) (Ad = 2-adamantyl, bdt = benzene-1,2-dithiolate). These complexes have square pyramidal structures with apical oxo ligands, exhibit rhombic EPR spectra, and 3-5 are electrochemically reducible to Mo(IV)O species. Complexes 1-6 constitute the first examples of five-coordinate monodithiolene Mo(V)O complexes; 6 approaches the proposed structure of the high-pH form of sulfite oxidase. Treatment of [MoO(2)(OSiPh(3))(2)] with Li(2)(bdt) in THF affords [MoO(2)(OSiPh(3))(bdt)](1-) (8). Reaction of 8 with 2,4,6-Pr(i)(3)C(6)H(2)SH in acetonitrile gives [MoO(2)(SC(6)H(2)-2,4,6-Pr(i)(3))(bdt)](1-) (9, 55%). Complexes 8 and 9 are square pyramidal with apical and basal oxo ligands. With one dithiolene and one thiolate ligand of a square pyramidal Mo(VI)O(2)S(3) coordination unit, 9 closely resembles the oxidized sites in sulfite oxidase and assimilatory nitrate reductase as deduced from crystallography (sulfite oxidase) and Mo EXAFS. The complex is the first structural analogue of the active sites in fully oxidized members of the sulfite oxidase family. This work provides a starting point for the development of both structural and reactivity analogues of members of this family.
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Chen Z, Li H, Dong W, Miao M, Ren H. I2-Catalyzed Oxidative Coupling Reactions of Hydrazones and Amines and the Application in the Synthesis of 1,3,5-Trisubstituted 1,2,4-Triazoles. Org Lett 2016; 18:1334-7. [DOI: 10.1021/acs.orglett.6b00277] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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6
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Miao M, Zhou X, Li Y, Zhang O, Zhou Z, Li T, Yuan W, Li R, Li DK. LINE-1 hypomethylation in spermatozoa is associated with Bisphenol A exposure. Andrology 2013; 2:138-44. [PMID: 24293158 DOI: 10.1111/j.2047-2927.2013.00166.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 10/24/2013] [Accepted: 10/29/2013] [Indexed: 11/30/2022]
Abstract
Bisphenol A (BPA) is an endocrine disruptor with potentially harmful effects on humans. However, epigenetic mechanisms that modulate the effects of BPA remain unclear. Methylation of long interspersed nucleotide elements (LINE-1) is a marker of genome-wide methylation status. This study aims to examine whether BPA exposure was associated with LINE-1 methylation changes in men. Male factory workers in Hunan, China (N = 149) were studied, 77 with BPA exposure in workplace (BPA-exposed group) and 72 without BPA exposure in workplace (control group). Pre-shift and post-shift urine samples were collected from the BPA-exposed group and spot urine samples were collected from the control group. Urine samples were assessed for BPA. In addition, blood and semen samples were collected from both groups for LINE-1 methylation analysis. In multivariate analysis adjusted for age, education, smoking habits and alcohol consumption, sperm LINE-1 methylation level was significantly lower in BPA exposed workers (p < 0.001) compared to that in the unexposed workers. Linear regression analysis also showed that log-transformed urine BPA levels were inversely associated with sperm LINE-1 methylation (p < 0.0001), but not peripheral blood cell LINE-1 methylation. Moreover, the association between urine BPA level and semen quality was not attenuated after adjustments for LINE-1 level. In summary, the observed independent relationship between BPA exposure and LINE-1 methylation may have public health implications on reproductive health in men because of ubiquitous exposure to BPA.
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Research Support, Non-U.S. Gov't |
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58 |
7
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Xu J, Yuan S, Peng J, Miao M, Chen Z, Ren H. Enantioselective [2+2] annulation of simple aldehydes with isatin-derived ketimines via oxidative N-heterocyclic carbene catalysis. Chem Commun (Camb) 2017; 53:3430-3433. [DOI: 10.1039/c7cc01232b] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An unprecedented [2+2] annulation of aldehydes with ketimines to afford enantioenriched spirooxindole β-lactams via oxidative NHC catalysis is disclosed.
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Miao M, Bruce AEE, Bhanji T, Davis EC, Keeley FW. Differential expression of two tropoelastin genes in zebrafish. Matrix Biol 2006; 26:115-24. [PMID: 17112714 DOI: 10.1016/j.matbio.2006.09.011] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Revised: 09/19/2006] [Accepted: 09/19/2006] [Indexed: 11/15/2022]
Abstract
Elastin is the extracellular matrix protein responsible for properties of extensibility and elastic recoil in large blood vessels, lung and skin of most vertebrates. Elastin is synthesized as a monomer, tropoelastin, but is rapidly transformed into its final polymeric form in the extracellular matrix. Until recently information on sequence and developmental expression of tropoelastins was limited to mammalian and avian species. We have recently identified and characterized two expressed tropoelastin genes in zebrafish. This was the first example of a species with multiple tropoelastin genes, raising the possibility of differential expression and function of these tropoelastins in elastic tissues of the zebrafish. Here we have investigated the temporal expression and tissue distribution of the two tropoelastin genes in developing and adult zebrafish. Expression was detected early in skeletal cartilage structures of the head, in the developing outflow tract of the heart, including the bulbus arteriosus and the ventral aorta, and in the wall of the swim bladder. While the temporal pattern of expression was similar for both genes, the upregulation of eln2 was much stronger than that of eln1. In general, both genes were expressed and their gene products deposited in most of the elastic tissues examined, with the notable exception of the bulbus arteriosus in which eln2 expression and its gene product was predominant. This finding may represent a sub-specialization of eln2 to provide the unique architecture of elastin and the specific mechanical properties required by this organ.
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Research Support, Non-U.S. Gov't |
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Xu J, Yuan S, Miao M, Chen Z. 1-Hydroxybenzotriazole-Assisted, N-Heterocyclic Carbene Catalyzed β-Functionalization of Saturated Carboxylic Esters: Access to Spirooxindole Lactones. J Org Chem 2016; 81:11454-11460. [PMID: 27709941 DOI: 10.1021/acs.joc.6b02032] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A 1-hydroxybenzotriazole-assisted, N-heterocyclic carbene catalyzed direct β-functionalization of saturated carboxylic esters is disclosed. This formal [3 + 2] annulation reaction of carboxylic esters with isatins affords optically pure spirooxindole lactones (on gram scale) bearing two vicinal stereogenic centers. A dual role of HOBt is proposed based on controlled experiments to rationalize the enhancement of diastereoselectivity and enantioselectivity.
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Research Support, Non-U.S. Gov't |
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48 |
10
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Miao M, Cao J, Zhang J, Huang X, Wu L. PdCl2-Catalyzed Oxidative Cycloisomerization of 3-Cyclopropylideneprop-2-en-1-ones. Org Lett 2012; 14:2718-21. [DOI: 10.1021/ol300927n] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wiss DA, Johnson DL, Miao M. Compression plating for non-union after failed external fixation of open tibial fractures. J Bone Joint Surg Am 1992. [DOI: 10.2106/00004623-199274090-00001] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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33 |
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Wong SW, Han D, Zhang H, Liu Y, Zhang X, Miao MZ, Wang Y, Zhao N, Zeng L, Bai B, Wang YX, Liu H, Frazier-Bowers SA, Feng H. Nine Novel PAX9 Mutations and a Distinct Tooth Agenesis Genotype-Phenotype. J Dent Res 2017; 97:155-162. [PMID: 28910570 DOI: 10.1177/0022034517729322] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Tooth agenesis is one of the most common developmental anomalies affecting function and esthetics. The paired-domain transcription factor, Pax9, is critical for patterning and morphogenesis of tooth and taste buds. Mutations of PAX9 have been identified in patients with tooth agenesis. Despite significant progress in the genetics of tooth agenesis, many gaps in knowledge exist in refining the genotype-phenotype correlation between PAX9 and tooth agenesis. In the present study, we complete genetic and phenotypic characterization of multiplex Chinese families with nonsyndromic (NS) tooth agenesis. Direct sequencing of polymerase chain reaction products revealed 9 novel (c.140G>C, c.167T>A, c.332G>C, c.194C>A, c.271A>T, c.146delC, c.185_189dup, c.256_262dup, and c.592delG) and 2 known heterozygous mutations in the PAX9 gene among 120 probands. Subsequently, pedigrees were extended, and we confirmed that the mutations co-segregated with the tooth agenesis phenotype (with exception of families in which DNA analysis was not available). In 1 family ( n = 6), 2 individuals harbored both the PAX9 c.592delG mutation and a heterozygous missense mutation (c.739C>T) in the MSX1 gene. Clinical characterization of families segregating a PAX9 mutation reveal that all affected individuals were missing the mandibular second molar and their maxillary central incisors are most susceptible to microdontia. A significant reduction of bitter taste perception was documented in individuals harboring PAX9 mutations ( n = 3). Functional studies revealed that PAX9 haploinsufficiency or a loss of function of the PAX9 protein underlies tooth agenesis.
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Research Support, Non-U.S. Gov't |
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39 |
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Yuan S, Luo Y, Peng J, Miao M, Xu J, Ren H. Oxidative Asymmetric [2 + 3] Annulation of Aldehydes with Azomethine Imines Enabled by N-Heterocyclic Carbene Catalysis. Org Lett 2017; 19:6100-6103. [DOI: 10.1021/acs.orglett.7b02948] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Low WK, Miao M, Ewart KV, Yang DS, Fletcher GL, Hew CL. Skin-type antifreeze protein from the shorthorn sculpin, Myoxocephalus scorpius. Expression and characterization of a Mr 9, 700 recombinant protein. J Biol Chem 1998; 273:23098-103. [PMID: 9722537 DOI: 10.1074/jbc.273.36.23098] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A cDNA clone encoding a presumptive antifreeze protein was isolated from a skin library from shorthorn sculpin, Myoxocephalus scorpius. The clone encodes a 92-residue mature polypeptide (sssAFP-2) without any signal and prosequence, which suggests an intracellular localization. It is the largest alanine-rich, alpha-helical type I antifreeze protein known. A recombinant fusion protein containing an N-terminal-linked His-tag was produced and purified from Escherichia coli. This protein is alpha-helical at 0 degreesC and exhibits significant antifreeze activity. Northern blot and reverse transcription-polymerase chain reaction analyses indicate that sssAFP-2 mRNA has limited tissue distribution and is present in peripheral tissues such as skin and dorsal fin, but is notably absent in the liver. These studies reinforce recent evidence that indicate that the external tissues of cold water marine fishes are major organs for antifreeze protein synthesis and are likely the first line of defense against the threat of freezing.
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Comparative Study |
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Xu J, Luo Y, Xu H, Chen Z, Miao M, Ren H. Catalyst-Controlled Chemodivergent Modification of Indoles with 2-Furylcarbinols: Piancatelli Reaction vs Cross-Dehydrative Coupling Reaction. J Org Chem 2017; 82:3561-3570. [PMID: 28244319 DOI: 10.1021/acs.joc.7b00090] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A divergent synthetic strategy to functionalize the indole nucleus with readily available 2-furylcarbinols was developed. It was found that the 3-(4-oxo-2-cyclopentenyl)indoles were obtained in moderate to good yields (up to 89%) through Piancatelli reaction catalyzed by ZnCl2, whereas employment of Brønsted acid TFA afforded directly coupled product 3-(2-furyl)indoles in moderate to good yields (up to 87%) via the deprotonation-rearomatization route.
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Research Support, Non-U.S. Gov't |
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30 |
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Xu J, Yuan S, Peng J, Miao M, Chen Z, Ren H. Base-mediated diastereoselective [4 + 3] annulation of in situ generated ortho-quinone methides with C,N-cyclic azomethine imines. Org Biomol Chem 2018; 15:7513-7517. [PMID: 28869260 DOI: 10.1039/c7ob01783a] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient [4 + 3] annulation of 2-(1-tosylalkyl)phenols with C,N-cyclic azomethine imines via in situ generation of ortho-quinone methides (o-QMs) under mild basic reaction conditions is disclosed, furnishing biologically interesting seven-membered heterocyclic compounds with moderate to good yields and excellent diastereoselectivities. A gram-scale reaction is performed to demonstrate the potential in industrial application and two transition states are proposed to rationalize the outstanding diastereoselectivity.
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Journal Article |
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Ren H, Dong W, Chen Z, Xu J, Miao M. Synthesis of Benzo-Fused Cyclic Compounds via Intramolecular Cyclization of Aryltriazenes. Synlett 2016. [DOI: 10.1055/s-0035-1561358] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Miao M, Xu H, Jin M, Chen Z, Xu J, Ren H. 1,2-Gold Carbene Transfer Empowers Regioselective Synthesis of Polysubstituted Furans. Org Lett 2018; 20:3096-3100. [PMID: 29733215 DOI: 10.1021/acs.orglett.8b01152] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A gold-catalyzed cascade cycloisomerization/ring-opening reaction of allenyl ketones bearing a cyclopropyl moiety with a wide variety of alcohols or ketones is developed. This reaction involves an unprecedented 1,2-gold carbene transfer to provide regioselective and modular access to tri- or tetrasubstituted furans in moderate to high yields and with broad substrate tolerability.
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Research Support, Non-U.S. Gov't |
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29 |
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Yang W, Yang Z, Xu L, Zhang L, Xu X, Miao M, Ren H. Surfactant-type Brønsted acid catalyzed stereoselective synthesis of trans-3-alkenyl indazoles from triazenylaryl allylic alcohols in water. Angew Chem Int Ed Engl 2013; 52:14135-9. [PMID: 24353234 DOI: 10.1002/anie.201306632] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/07/2013] [Indexed: 11/09/2022]
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Research Support, Non-U.S. Gov't |
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28 |
20
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Yi Z, Chen Z, Warren A, Roberts D, Al-Rasheid KAS, Miao M, Gao S, Shao C, Song W. Molecular phylogeny ofPseudokeronopsis(Protozoa, Ciliophora, Urostylida), with reconsideration of three closely related species at inter- and intra-specific levels inferred from the small subunit ribosomal RNA gene and the ITS1-5.8S-ITS2 region sequences. J Zool (1987) 2008. [DOI: 10.1111/j.1469-7998.2008.00438.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Miao M, Cao J, Zhang J, Huang X, Wu L. Cu(I)-Catalyzed Domino Reaction of 3-Cyclopropylideneprop-2-en-1-ones. J Org Chem 2013; 78:2687-92. [PMID: 23414339 DOI: 10.1021/jo302312y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26 |
22
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Low WK, Lin Q, Stathakis C, Miao M, Fletcher GL, Hew CL. Isolation and characterization of skin-type, type I antifreeze polypeptides from the longhorn sculpin, Myoxocephalus octodecemspinosus. J Biol Chem 2001; 276:11582-9. [PMID: 11136728 DOI: 10.1074/jbc.m009293200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The antifreeze polypeptides (AFPs) are found in several marine fish and have been grouped into four distinct biochemical classes (type I-IV). Recently, the new subclass of skin-type, type I AFPs that are produced intracellularly as mature polypeptides have been identified in the winter flounder (Pleuronectes americanus) and the shorthorn sculpin (Myoxocephalus scorpius). This study demonstrates the presence of skin-type AFPs in the longhorn sculpin (Myoxocephalus octodecemspinosus), which produces type IV serum AFPs. Using polymerase chain reaction-based methods, a clone that encoded for a type I AFP was identified. The clone lacked a signal sequence, indicating that the mature polypeptide is produced in the cytosol. A recombinant protein was produced in Escherichia coli and antifreeze activity was characterized. Four individual Ala-rich polypeptides with antifreeze activity were isolated from the skin tissue. One polypeptide was completely sequenced by tandem MS. This study provides the first evidence of a fish species that produces two different biochemical classes of antifreeze proteins (type I and type IV), and enforces the notion that skin-type AFPs are a widespread biological phenomenon in fish.
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Miao M, Willer MW, Holm RH. Oxo/sulfidotungstate(VI) as precursors to W(VI)O2, W(VI)OS, and W(VI)S2 complexes and W(IV)-dithiolene chelate rings. Inorg Chem 2000; 39:2843-9. [PMID: 11232822 DOI: 10.1021/ic000047l] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Synthetic models leading to oxosulfidotungsten(VI) groups and dithiolene chelate rings have been investigated. The heterogeneous reaction systems [WO4-nSn]2-/2Ph3SiCl/Me4phen (n = 0-2) in acetonitrile afford the complexes [WQ2(OSiPh3)2(Me4phen)] (1-3) in the indicated yields containing the groups W(VI)O2 (1; 86%), W(VI)O2 (2; 45%), and W(VI)S2 (3; 83%). In the crystalline state these complexes have imposed C2 symmetry, with cis-oxo/sulfido and trans-silyloxide ligands. 1H NMR spectra indicate that this stereochemistry is retained in solution. The colors of 2 (yellow, 367 nm) and 3 (orange, 451 nm) arise from LMCT absorptions at the indicated wavelengths. These results demonstrate that the silylation procedure previously introduced for the preparation of molecules with the Mo(VI)OS group (Thapper, et al. Inorg. Chem. 1999, 38, 4104) extends to tungsten. Methods for the formation of dithiolene chelate rings MS2C2R2 in reactions with sulfide-bound M = Mo or W precursors are summarized. In a known reaction type, 3 and activated acetylenes rapidly form [W(IV)(OSiPh3)2(Me4phen)(S2C2R2)] (R = CO2Me, 4, 83%, and Ph, 5, 98%). In a new reaction type not requiring the isolation of an intermediate, the systems [MO2S2]2-/2Ph3SiCl/Me4phen/PhC=CPh in acetonitrile afford 5 (68%) and [Mo(IV)(OSiPh3)2(Me4phen)(S2C2Ph2)] (6; 61%). Complexes 5 and 6 are isostructural, maintain the trans-silyloxide stereochemistry, and exhibit chelate ring dimensions indicative of ene- 1,2-dithiolate coordination. Reductions in the -1.4 to -1.7 V range are described as metal-centered. It remains to be seen whether the oxo/sulfidotungsten(VI) groups in 1-3 eventuate in the active sites of tungstoenzymes. (Me4phen = 3,4,7,8-tetramethyl-1,10-phenanthroline.)
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Xu L, Yang W, Zhang L, Miao M, Yang Z, Xu X, Ren H. Brönsted Acid-Mediated Intramolecular Cyclization of Biaryl Triazenes for the Synthesis of Fluorenes and 9,10-Dihydro-Phenanthrenes. J Org Chem 2014; 79:9206-21. [DOI: 10.1021/jo501640d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Zhang S, Tang A, Chen P, Zhao Z, Miao M, Ren H. Tunable Gold(I)-Catalyzed [4 + 3] Cycloaddition for Divergent Synthesis of Furan-Fused N,O-Heterocycles. Org Lett 2020; 22:848-853. [DOI: 10.1021/acs.orglett.9b04312] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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