bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heads‐up: New roles for the fragile X mental retardation protein in neural stem and progenitor cells
Authors: Callan Matthew A. , Zarnescu Daniela C. 
Published: March 2011

AbstractFragile X syndrome (FXS) is the most common form of inherited mental retardation and is caused by the loss of function for Fragile X Mental Retardation Protein (FMRP), a selective RNA‐binding protein with a demonstrated role in the localized translation of target mRNAs at synapses. Several recent studies provide compelling evidence for a new role of FMRP in the development of the nervous system, during neurogenesis. Using a multi‐faceted approach and a variety of model systems ranging from cultured neurospheres and progenitor cells to in vivoDrosophilaand mouse models these reports indicate that FMRP is required for neural stem and progenitor cell proliferation, differentiation, survival, as well as regulation of gene expression. Here we compare and contrast these recent reports and discuss the implications of FMRP's new role in embryonic and adult neurogenesis, including the development of novel therapeutic approaches to FXS and related neurological disorders such as autism. genesis 49:424–440,2011. © 2011 Wiley‐Liss, Inc.
Formation Mechanism of Head‐to‐Head Amidato‐Bridged Acetonylplatinum(III) Binuclear Complexes – Kinetic Evidence for π‐Coordination of the Enol Form of a Ketone in a Ligand Substitution Reaction
Authors: Fukushima Hiroyuki , Mori Hiroki , Arime Moritatsu , Iwatsuki Satoshi , Ishihara Koji , Matsumoto Kazuko 
Published: March 2011

AbstractReactions of head‐to‐head (HH) α‐pyridonato‐ and pivalamidato‐bridged platinum(III) binuclear complexes withacetone were investigated kinetically. The reactions with acetone proceeded slowly to form acetonyl PtIII binuclear complexes in two steps. A mechanism, which involves π‐coordination of the enol form of acetone in the first step, followed by the π–σ bond conversion in the second step, is proposed. π‐Coordination of the enol was strongly supported by kinetic analyses of a ligand substitution reaction involving the pivalamidato‐bridged PtIII binuclear complex with (4‐hydroxyphenyl)pyruvic acid. Only the enol form was reactive towards the PtIII dimer complex.
Sulfuric Acid‐Catalyzed Regioselective Alkylation of Indoles and β‐Naphthols with Ketene Dithioacetal‐Based Allylic Alcohols
Authors: Wang Mang , Sun Shaoguang , Liang Deqiang , Liu Bangyu , Dong Ying , Liu Qun 
Published: March 2011

AbstractA novel catalytic alkylation of indoles with allylic alcohols has been developed. Catalyzed by sulfuric acid (10 mol‐%), the reaction between indoles 2 and allylic alcohols 1 based on ketene dithioacetal affords polyfunctionalized indoles 3 in good to excellent yields with high regioselectivities under mild conditions. The catalytic carbon–carbon coupling reaction provides a facile method for the environmentally benign functionalization of indoles with the advantages of good regiochemistry, atom efficiency, easily available catalyst, good yields and the synthetic potential of the polyfunctionalized indole products. Thus, further transformation of the resulting indoles 3 into pyridoindolone derivatives 4 was investigated. The efficiency of this carbon–carbon coupling reaction of 1 with 2 under the catalysis of sulfuric acid is due to the efficient formation of the reactive intermediate I, which is a carbocation that is strongly stabilized by two alkylthio groups at the terminal of the carbon–carbon double bond. The extension of this catalytic strategy to the synthesis of β‐naphthols 5 was also achieved.
A New and Efficient Synthesis of Derivatives of Octahydro‐4H‐pyrrolo[1,2‐c]pyrido[1′,2′‐a]imidazole
Authors: Rouchaud Anne , Braekman Jean‐Claude 
Published: March 2011

AbstractWhen diethyl malonate was added to a solution of Δ1‐piperideine, generated in situ by oxidative desamination and decarboxylation of L‐lysine by N‐bromosuccinimide (NBS), formation of the unexpected tricyclic compound 6 (4‐diethylmalonyl‐octahydro‐4H‐pyrrolo[1,2‐c]pyrido[1′,2′‐a]imidazole)was observed. The structure of 6 was deduced from analysis of its spectroscopic data and was confirmed both by chemical degradation and by total synthesis. We proved that 3‐bromo‐1‐piperideine was implicated in its formation. Moreover, based on this feature, a new and efficient synthesis of 6 was developed. The elaborated pathway was adapted to access derivatives related to 6 that differed in their C‐4 substituent.
Homocoupling of Arylboronic Acids Catalyzed by CuCl in Air at Room Temperature
Authors: Cheng Guanjun , Luo Meiming 
Published: March 2011

AbstractHomocoupling of arylboronic acids has been successfully carried out by using the inexpensive simple copper salt CuCl as the catalyst in methanol to obtain symmetric biaryls in good to excellent yields. The reaction proceeds with a CuCl loading of 2 mol‐% under extremely mild conditions: in air, at room temperature, without the need of any additives such as base, oxidant, or ligand.
Socially motivated projection: Need to belong increases perceived opinion consensus on important issues
Authors: Morrison Kimberly Rios , Matthes Jörg 
Published: March 2011

AbstractIn three studies, we tested whether the need to belong would motivate people to perceive consensus for their opinions on important social issues. In Study 1, a nationally representative telephone survey, participants with a high dispositional need to belong perceived greater consensus for their opinions on immigrant naturalization than did those with a low need to belong. However, this relationship was strongest among participants who reported that the issue was personally important to them. In Study 2, participants primed with rejection‐related (versus acceptance‐related) words, and who reported high levels of issue importance, demonstrated greater false consensus for their opinions on a proposed alcohol tax increase. In Study 3, participants who received random feedback that they held a common (versus uncommon) opinion had a lower subsequent need to belong when the issue was important to them, suggesting that consensus perceptions can in fact mitigate belongingness needs. Copyright © 2011 John Wiley & Sons, Ltd.
Extremely large displacement dynamic analysis of elastic–plastic plane frames
Authors: Wang Ren‐Zuo , Tsai Keh‐Chyuan , Lin Bo‐Zhou 
Published: March 2011

AbstractThis paper presents a numerical analysis of large displacement responses of elastic–plastic plane frames under static and dynamic loads, by applying the vector‐form intrinsic finite element (VFIFE or V‐5) method. The VFIFE method defines the structure into a number of mass points, and applies Newton's second law and the internal force equilibrium to describe the motions of each mass point. By tracing the motions of all the mass points, it can analyze the large geometrical and material nonlinear changes during the motion of the structure without using the geometrical stiffness matrix and iterative procedures. Three different numerical examples are presented to demonstrate both the capability and the accuracy of the VFIFE method in a nonlinear dynamic analysis of frame structures with extremely large displacement. Copyright © 2011 John Wiley & Sons, Ltd.
Explicit Weight Stereotypes Are Curvilinear: Biased Judgments of Thin and Overweight Targets
Authors: Malloy Thomas E. , Lewis Beth , Kinney Lorin , Murphy Peter 
Published: March 2011

AbstractBias against overweight people is documented; however, little attention has been directed to bias against thin people. Theoretically, light and heavy bodies can invoke an affective mechanism leading to bias and avoidance of those different physically from the average. Participants (N = 62) rated six same or opposite sex targets varying randomly in weight. Ratings of traits and liking were curvilinear as a function of weight and showed bias against light and heavy targets. For heavy targets, negative affect predicted discriminatory behavioural intentions; stereotypes did not. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
The Turkish Version of the Eating Disorder Examination Questionnaire: Reliability and Validity in Adolescents
Authors: Yucel Basak , Polat Aslihan , Ikiz Tevfika , Dusgor Bengi Pirim , Elif Yavuz Ayse , Sertel Berk Ozlem 
Published: March 2011

AbstractThe Eating Disorder Examination Questionnaire (EDE‐Q) is the self‐report questionnaire version of the Eating Disorder Examination Interview. The aim of the current study was to validate a Turkish version of the EDE‐Q in a sample of Turkish primary and high school students (626 girls and 299 boys) in Istanbul. Subjects also completed the Eating Attitudes Test, the General Health Questionnaire and the Body Image Satisfaction Questionnaire, and they were weighed. Girls had higher scores on all EDE‐Q subtests. EDE‐Q scores increased as body mass ındex increased. EDE‐Q total score and subscales were highly correlated with the Eating Attitudes Test and the Body Image Satisfaction Questionnaire, supporting its validity. A small test–retest reliability study provided satisfactory results. The present study suggests that the Turkish version of EDE‐Q is an acceptable, reliable and valid measure in nonclinical adolescent samples. More psychometric studies are needed concerning wider age ranges and various clinical samples. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
Flow modelling in gravel‐bed rivers: rethinking the bottom boundary condition
Authors: Rameshwaran Ponnambalam , Naden Pamela S , Lawless Mark 
Published: March 2011

ABSTRACTA key problem in computational fluid dynamics (CFD) modelling of gravel‐bed rivers is the representation of multi‐scale roughness, which spans the range from grain size, through bedforms, to channel topography. These different elements of roughness do not clearly map onto a model mesh and use of simple grain‐scale roughness parameters may create numerical problems. This paper presents CFD simulations for three cases: a plane bed of fine gravel, a plane bed of fine gravel including large, widely‐spaced pebble clusters, and a plane gravel bed with smaller, more frequent, protruding elements. The plane bed of fine gravel is modelled using the conventional wall function approach. The plane bed of fine gravel including large, widely‐spaced pebble clusters is modelled using the wall function coupled with an explicit high‐resolution topographic representation of the pebble clusters. In these cases, the three‐dimensional Reynolds‐averaged continuity and Navier–Stokes equations are solved using the standard k − ε turbulence model, and model performance is assessed by comparing predicted results with experimental data. For gravel‐bed rivers in the field, it is generally impractical to map the bed topography in sufficient detail to enable the use of an explicit high‐resolution topography. Accordingly, an alternative model based on double‐averaging is developed. Here, the flow calculations are performed by solving the three‐dimensional double‐averaged continuity and Navier‐Stokes equations with the spatially‐averaged 〈k − ε〉 turbulence model. For the plane bed of fine gravel including large, widely‐spaced pebble clusters, the model performance is assessed by comparing the spatially‐averaged velocity with the experimental data. The case of a plane gravel bed with smaller, more frequent, protruding elements is represented by a series of idealized hypothetical cases. Here, the spatially‐averaged velocity and eddy viscosity are used to investigate the applicability of the model, compared with using the explicit high‐resolution topography. The results show the ability of the model to capture the spatially‐averaged flow field and, thus, illustrate its potential for representing flow processes in natural gravel‐bed rivers. Finally, practical data requirements for implementing such a model for a field example are given. Copyright © 2011 John Wiley & Sons, Ltd.
As time goes by: Hippocampal connectivity changes with remoteness of autobiographical memory retrieval
Authors: Söderlund Hedvig , Moscovitch Morris , Kumar Namita , Mandic Marina , Levine Brian 
Published: March 2011

AbstractThe hippocampus is crucial for episodic autobiographical memory retrieval. Functional neuroimaging evidence suggests that it is similarly engaged in recent and remote retrieval when memories are matched on vividness and personal importance. Far fewer studies have investigated the nature of hippocampal‐neocortical coactivation in relation to memory remoteness. The purpose of this study was to examine hippocampal activity and functional connectivity as a function of memory age. Unlike most studies of autobiographical memory, we included autobiographical memories formed in the days and weeks before scanning, in addition to truly remote memories on the order of months and years. Like previous studies, we found that the hippocampus was active bilaterally regardless of memory age, with anterior activity increasing up to 1 yr and then decreasing, and with posterior activity being less sensitive to memory age. More importantly, hippocampal functional connectivity varied with memory age. Retrieving recent memories (≤1 yr) showed a late coactivation of the hippocampus and areas of the autobiographical memory network, whereas retrieving remote memories (10 yrs) showed an early negative coactivation of the hippocampus and left inferior frontal gyrus followed by a positive coactivation with anterior cingulate. This finding may reflect that the hippocampus is more strongly integrated with the autobiographical memory network for recent than for remote memories, and that more effort is required to recover remote memories. © 2011 Wiley Periodicals, Inc.
Polyynes from Toona ciliata var. ciliata and Related Cytotoxic Activity
Authors: Ning Jing , Di Ying‐Tong , Li Shi‐Fei , Geng Zhao‐Liang , He Hong‐Ping , Wang Yue‐Hu , Wang Yuan‐Yuan , Li Yan , Li Shun‐Lin , Hao Xiao‐Jiang 
Published: March 2011

AbstractA phytochemical investigation of Toona ciliata var. ciliata afforded three new polyynes, 1–3. Their structures were elucidated on the basis of spectroscopic analysis and chemical methods. Only compound 3 exhibited potent cytotoxicity against the HL‐60 cell line with an IC50 value of 6.7±0.27 μM.
Splendidins A – C, Three New Clerodane Diterpenoids from Salvia splendens
Authors: Pan Zheng‐Hong , Cheng Jin‐Tang , He Juan , Wang Yuan‐Yuan , Peng Li‐Yan , Xu Gang , Sun Wei‐Bang , Zhao Qin‐Shi 
Published: March 2011

AbstractThree new clerodane diterpenoids, splendidins A–C (1–3, resp.), were isolated from Salvia splendens, together with six known ones. Their structures were elucidated by extensive spectroscopic analysis. Splendidin C (3) was the first diterpenoid glucoside reported from this plant. These compounds were evaluated for their cytotoxic activity; however, none of them were cytotoxic.
New Isoflavone C‐Glycosides from Pueraria lobata
Authors: Li Guo‐Hui , Zhang Qing‐Wen , Wang Lei , Zhang Xiao‐Qi , Ye Wei‐Cai , Wang Yi‐Tao 
Published: March 2011

AbstractThree new isoflavone C‐glycosides, along with two known isoflavone O‐glycosides, were isolated from the roots of Pueraria lobata (Willd.) Ohwi. The structures of the new compounds were elucidated as 4′,7‐dihydroxy‐3′‐methoxyisoflavone 8‐C‐[β‐d‐glucopyranosyl‐(1→6)]‐β‐d‐glucopyranoside (1), 4′,7‐dihydroxy‐3′‐methoxyisoflavone 8‐C‐[β‐d‐apiofuranosyl‐(1→6)]‐β‐d‐glucopyranoside (2), and 8‐C‐β‐d‐glucopyranosyl‐4′,7‐dihydroxy‐3′‐methoxyisoflavone 4′‐O‐β‐d‐glucopyranoside (3) on the basis of spectroscopic methods, especially 2D‐NMR and MS analyses. The known compounds isolated were identified by comparison of their physical and spectroscopic data with those reported in the literature.
Caragisides A – C, New Isoflavone Glucosides from Caragana conferta with Inhibition of Platelet Aggregation
Authors: Nisar Khan Amna , Fatima Itrat , Malik Abdul , Rasheed Huma 
Published: March 2011

AbstractCaragisides A–C (1–3, resp.), three new isoflavone glucosides, were isolated from the BuOH sub‐fraction of the EtOH extract of the whole plant of Caragana conferta, along with ononoside (4), reported for the first time from this species. The structures of the new compounds were elucidated by spectroscopic techniques including MS and 2D‐NMR spectroscopy. Compounds 1–3 showed significant inhibition of platelet aggregation.
Synthesis of Dialkyl 2‐(Alkylamino)‐4,9‐dihydro‐9‐oxocyclohepta[b]pyran‐3,4‐dicarboxylates
Authors: Azizian Javad , Ramazani Ali , Haji Mohammad 
Published: March 2011

AbstractDialkyl 2‐(alkylamino)‐4,9‐dihydro‐9‐oxocyclohepta[b]pyran‐3,4‐dicarboxylates are prepared in a one‐pot three‐component reaction of alkyl isocyanide, dialkyl acetylenedicarboxylate, and α‐tropolone (=2‐hydroxycyclohepta‐2,4,6‐trienone). The reaction proceeds smoothly at room temperature and under neutral conditions to afford tropolone derivatives in high yield.
Two New Flavonoids from the Rhizomes of Abacopteris penangiana
Authors: Zhao Zhongxiang , Ruan Jinlan , Jin Jing , Zhu Chenchen , Yu Yang 
Published: March 2011

AbstractA new flavan‐4‐ol glycoside, abacopterin K (1), and a new dihydrochalcone glycoside, abacopterin L (2), were isolated from the rhizomes of Abacopteris penangiana. Their structures were elucidated on the basis of various spectroscopic analyses and chemical evidences. The novel glucosylation pattern of abacopterin K consisting of two ‘glucose‐fused’ dioxepine ring moieties is found for the first time within natural flavonoids.
Novel Four‐Component Approach for the Synthesis of Polyfunctionalized 1,4‐Dihydropyridines in Aqueous Media
Authors: Hadjebi Melika , Hashtroudi Mehri S. , Bijanzadeh Hamid Reza , Balalaie Saeed 
Published: March 2011

AbstractThe four‐component reaction of dimethyl acetylenedicarboxylate (=dimethyl but‐2‐ynedioate; DMAD), aromatic aldehydes, and malononitrile (=propanedinitrile) leads to polyfunctionalized 1,4‐dihydropyridine derivatives. The reaction proceeds at room temperature and in the presence of a catalytic amount (20%) of (NH4)2HPO4 as a base in aqueous media.
Chemical Constituents from Fruits and Stem Bark of Celtis australis L.
Authors: Badoni Ruchi , Kumar Semwal Deepak , Rawat Usha , Singh Maniyari Rawat Mohan 
Published: March 2011

AbstractFour triterpenoids named (9β,31R)‐9,25‐cyclo‐30‐propylhopan‐31‐ol (1), (3β)‐3‐hydroxy‐30‐propylhopan‐31‐one (2), (3β)‐oleanan‐3‐ol (3), and (3β,9β)‐9,25‐cycloolean‐12‐en‐3‐yl β‐D‐glucofuranoside (4), a steroid named (3β,9β,14β)‐14‐hydroxy‐9,19‐cyclocholan‐3‐yl β‐D‐glucopyranoside (5), and an anthraquinone named 6‐hydroxy‐5,7,8‐trimethoxy‐9,10‐dioxo‐9,10‐dihydroanthracen‐2‐yl acetate (6) have been isolated from the fruits and bark of Celtis australis (Ulmaceae), along with apigenin, quercetin, and its glucoside. Their structures were elucidated by means of chemical and spectral analysis including COSY, NOESY, and HMBC experiments.
Synthesis of a Novel Series of 2,3‐Disubstituted Quinazolin‐4(3H)‐ones as a Product of a Nucleophilic Attack at C(2) of the Corresponding 4H‐3,1‐Benzoxazin‐4‐one
Authors: El‐Hashash Mahr A. , El‐Badry Yaser A. 
Published: March 2011

AbstractA new series of 2,3‐disubstituted quinazolin‐4(3H)‐one derivatives was synthesized by nucleophilic attack at C(2) of the corresponding key starting material 2‐propyl‐4H‐3,1‐benzoxazin‐4‐one (Scheme 2). The reaction proceeded via amidinium salt formation (Scheme 3) rather than via an N‐acylanthranilimide. The structure of the prepared compounds were elucidated by physical and spectral data like FT‐IR, 1H‐NMR, and mass spectroscopy.
New Eremophilenolides from Senecio dianthus
Authors: Li Yan‐Hui , Zhou Yan , Suolang Gesang , Bianba Ciren , Ding Li‐Sheng , Feng Hui 
Published: March 2011

AbstractFrom the aerial parts of Senecio dianthus, four new eremophilenolides (1–4, resp.) and one new eremophilenolide alkaloid (5), of the relatively uncommon eremophilenoid‐type sesquiterpenoid lactones, were isolated together with three known sesquiterpenoid lactones, 10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide (6), 8β,10β‐dihydroxyeremophil‐7(11)‐en‐12,8α‐olide (7), and 10α‐hydroxy‐1‐oxoeremophila‐7(11),8(9)‐dien‐12,8‐olide (8). On the basis of IR, MS, and NMR data, particularly 2D‐NMR analyses, the structures of the new compounds were established as: 2β‐(angeloyloxy)‐10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide (1), 6β‐(angeloyloxy)‐10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide (2), 2β‐(angeloyloxy)‐8β,10β‐dihydroxyeremophil‐7(11)‐en‐12,8α‐olide (3), 2β‐(angeloyloxy)‐8α‐hydroxyeremophila‐7(11),9(10)‐dien‐12,8β‐olide (4), and 8β‐amino‐10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide (5). In addition, the relative configuration of 1 was corroborated by X‐ray diffraction analysis.
Two Antioxidant Alkaloids from Portulaca oleracea L.
Authors: Liu Dianyu , Shen Tao , Xiang Lan 
Published: March 2011

AbstractTwo alkaloids, oleraceins F and G, were isolated from Portulaca oleracea L., and their structures were determined as methyl (2S)‐6‐[(β‐D‐glucopyranosyl)oxy]‐2,3‐dihydro‐5‐hydroxy‐1‐[(2E)‐3‐(4‐hydroxy‐3‐methoxyphenyl)prop‐2‐enoyl]‐1H‐indole‐2‐carboxylate and methyl (2S)‐6‐[(β‐D‐glucopyranosyl)oxy]‐2,3‐dihydro‐5‐hydroxy‐1‐[(2E)‐3‐(4‐hydroxyphenyl)prop‐2‐enoyl]‐1H‐indole‐2‐carboxylate, based on their spectroscopic data. Oleraceins F and G exhibited scavenging activity against 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical, with EC50 values of 21.00 and 37.69 μM, respectively.
Synthesis of Flavin–Calix[4]arene Conjugate Derivatives
Authors: Sayin Serkan , Uysal Akkuş Gülderen , Cibulka Radek , Stibor Ivan , Yilmaz Mustafa 
Published: March 2011

AbstractThe synthesis of two new flavin substituted calix[4]arene derivatives, 9 and 10, is described. The first flavin substituted calix[4]arene derivative 9 was synthesized by the reaction of 3‐methylalloxazine (5) with 25,27‐bis(3‐bromopropoxy)‐26,28‐dihydroxy‐5,11,17,23‐tetra(tert‐butyl)calix[4]arene (4) in high yield (92%). The other derivative 10 was prepared from 3‐methylalloxazine‐1‐acetic acid (7) and 25,27‐bis(3‐cyanopropoxy)calix[4]arene (3). All new compounds were characterized by a combination of FT‐IR and 1H‐NMR spectroscopy, and elemental‐analysis techniques.
Reactions of Verbenol Epoxide with Aromatic Aldehydes Containing Hydroxy or Methoxy Groups in the Presence of Montmorillonite Clay
Authors: Il'ina Irina V. , Volcho Konstantin P. , Mikhalchenko Oksana S. , Korchagina Dina V. , Salakhutdinov Nariman F. 
Published: March 2011

AbstractThe reactions of (−)‐cis‐verbenol epoxide with a number of aromatic aldehydes containing OH and/or MeO groups in the presence of montmorillonite K10 clay have been studied. Several new O‐containing heterocyclic compounds with different frameworks, including compounds with a previously unknown octahydro‐2H‐4,6‐(epoxymethano)chromene framework, have been synthesized. Introduction of one donor substituent in the benzaldehyde molecule led to a decrease in the total yield of intermolecular by formed products, while the introduction of two and more substituents led to an increase in the yield of these products.
Dimorphamides A – C, New Polyphenolic Amides from Atriplex dimorphostagia
Authors: Karim Aman , Fatima Itrat , Hussain Saghir , Malik Abdul 
Published: March 2011

AbstractDimorphamides A–C (1–3, resp.), three new polyphenolic amides, have been isolated from the BuOH‐soluble fraction of the whole plant of Atriplex dimorphostagia, along with two known compounds, thymidine and N‐[(E)‐feruloyl]tyramine. Their structures have been determined on the basis of spectral studies.
Terpenoids from the Chinese Liverwort Chiloscyphus polyanthus
Authors: Xie Chun‐Feng , Sun Bin , Guo Dong‐Xiao , Gao Jian , Qu Jian‐Bo , Lou Hong‐Xiang 
Published: March 2011

AbstractA new diterpene, (7α,11β,14β,16R)‐7,11,14‐trihydroxy‐ent‐kaur‐15‐one (1), and a new sesquiterpene, polyanthuslide (2), were isolated from the Chinese liverwort Chiloscyphus polyanthus. Their structures were determined on the basis of extensive spectroscopic analyses, and the configuration of 2 was established by X‐ray crystallographic analysis.