87681-25-2Relevant academic research and scientific papers
Intramolecular Diels-Alder reactions of silyl acetal trienes. The effect on stereoselectivity of allylic substitution
Craig,Reader
, p. 4073 - 4076 (1992)
The syntheses and thermal intramolecular Diels-Alder reactions of silyl acetal trienes possessing methyl groups at the allylic positions of the diene or dienophile are described. A model is proposed to account for the observed selectivities. The structure
A Series of (2S)-2-O-Protected-2-hydroxypropanals (L-Lactaldehydes) Suitable for Use as Optically Active Intermediates
Massad, Suhail K.,Hawkins, L. D.,Baker, David C.
, p. 5180 - 5182 (1983)
The synthesis and properties of a series of (2S)-2-O-protected-2-hydroxypropanals, where the protecting groups are tert-butyldimethylsilyl (3a), tert-butyldiphenylsilyl (3b), and (methoxyethoxy)methyl (3c), are described.A 1H NMR spectroscopic method of d
Self-Assembly and Molecular Recognition in Water: Tubular Stacking and Guest-Templated Discrete Assembly of Water-Soluble, Shape-Persistent Macrocycles
Wang, Qiuhua,Zhong, Yulong,Miller, Daniel P.,Lu, Xiaoxing,Tang, Quan,Lu, Zhong-Lin,Zurek, Eva,Liu, Rui,Gong, Bing
supporting information, p. 2915 - 2924 (2020/02/04)
Supramolecular chemistry in aqueous media is an area with great fundamental and practical significance. To examine the role of multiple noncovalent interactions in controlled assembling and binding behavior in water, the self-association of five water-soluble hexakis(m-phenylene ethynylene) (m-PE) macrocycles, along with the molecular recognition behavior of the resultant assemblies, is investigated with UV-vis, fluorescence, CD, and NMR spectroscopy, mass spectrometry, and computational studies. In contrast to their different extents of self-aggregation in organic solvents, all five macrocycles remain aggregated in water at concentrations down to the micromolar (μM) range. CD spectroscopy reveals that 1-F6 and 1-H6, two macrocycles carrying chiral side chains and capable of H-bonded self-association, assemble into tubular stacks. The tubular stacks serve as supramolecular hosts in water, as exemplified by the interaction of macrocycles 1-H6 and 2-H6 and guests G1 through G4, each having a rod-like oligo(p-phenylene ethynylene) (p-PE) segment flanked by two hydrophilic chains. Fluorescence and 1H NMR spectroscopy revealed the formation of kinetically stable, discrete assemblies upon mixing 2-H6 and a guest. The binding stoichiometry, determined with fluorescence, 1H NMR, and ESI-MS, reveals that the discrete assemblies are novel pseudorotaxanes, each containing a pair of identical guest molecules encased by a tubular stack. The two guest molecules define the number of macrocyclic molecules that comprise the host, which curbs the "infinite" stack growth, resulting in a tubular stack with a cylindrical pore tailoring the length of the p-PE segment of the bound guests. Each complex is stabilized by the action of multiple noncovalent forces including aromatic stacking, side-chain H-bonding, and van der Waals interactions. Thus, the interplay of multiple noncovalent forces aligns the molecules of macrocycles 1 and 2 into tubular stacks with cylindrical inner pores that, upon binding rod-like guests, lead to tight, discrete, and well-ordered tubular assemblies that are unprecedented in water.
Total Synthesis of the GRP78-Downregulatory Macrolide (+)-Prunustatin A, the Immunosuppressant (+)-SW-163A, and a JBIR-04 Diastereoisomer That Confirms JBIR-04 Has Nonidentical Stereochemistry to (+)-Prunustatin A
Manaviazar, Soraya,Nockemann, Peter,Hale, Karl J.
supporting information, p. 2902 - 2905 (2016/07/06)
A unified total synthesis of the GRP78-downregulator (+)-prunustatin A and the immunosuppressant (+)-SW-163A based upon [1 + 1 + 1 + 1]-fragment condensation and macrolactonization between O(4) and C(5) is herein described. Sharpless asymmetric dihydroxylation was used to set the C(2) stereocenter present in both targets. In like fashion, coupling of the (+)-prunustatin A macrolide amine with benzoic acid furnished a JBIR-04 diastereoisomer whose NMR spectra did not match those of JBIR-04, thus confirming that it has different stereochemistry than (+)-prunustatin A.
Total synthesis of (-)-pyrenophorol
Yadav, Jhillu S.,Reddy, Ganapuram Madhusudhan,Rao, Tenneti Srinivasa,Reddy, Basi V. Subba,Al Khazim Al Ghamdi, Ahmad
scheme or table, p. 783 - 787 (2012/04/10)
An efficient synthetic route has been developed for the synthesis of (-)-pyrenophorol employing Sharpless asymmetric epoxidation, olefin cross-metathesis, and intermolecular Mitsunobu cyclization. Georg Thieme Verlag Stuttgart · New York.
Stereochemical diversity of AI-2 analogs modulates quorum sensing in Vibrio harveyi and Escherichia coli
Rui, Fabio,Marques, Jo?o C.,Miller, Stephen T.,Maycock, Christopher D.,Xavier, Karina B.,Ventura, M. Rita
experimental part, p. 249 - 256 (2012/03/10)
Bacteria coordinate population-dependent behaviors such as virulence by intra- and inter-species communication (quorum sensing). Autoinducer-2 (AI-2) regulates inter-species quorum sensing. AI-2 derives from the spontaneous cyclisation of linear (S)-4,5-d
Synthesis of manzacidin A and C: Efficient construction of quaternary carbon stereocenters bearing nitrogen substituents
Ichikawa, Yoshiyasu,Okumura, Ken,Matsuda, Yasunori,Hasegawa, Tomoyuki,Nakamura, Mitsuhiro,Fujimoto, Aya,Masuda, Toshiya,Nakano, Keiji,Kotsuki, Hiyoshizo
experimental part, p. 614 - 622 (2012/02/05)
An efficient synthetic method for stereoselective construction of asymmetric quaternary carbon stereocenters, bearing nitrogen in the form of Boc-protected allyl amines, has been developed. This methodology is employed in the synthesis of marine alkaloids
A concise total synthesis of amphidinolide T2
Li, Huoming,Wu, Jinlong,Luo, Jialu,Dai, Wei-Min
supporting information; experimental part, p. 11530 - 11534 (2010/11/24)
RCM+AD=T2: In the presence of the C16-methylene group, regioselective ring-closing metathesis (RCM) formed the (12E)-endocyclic double bond, which underwent Os-catalyzed asymmetric dihydroxylation (AD) to give the desired 12,13-diol intermediate required
New insights into poly(lactic- co -glycolic acid) microstructure: Using repeating sequence copolymers to decipher complex NMR and thermal behavior
Stayshich, Ryan M.,Meyer, Tara Y.
supporting information; experimental part, p. 10920 - 10934 (2010/09/17)
Sequence, which Nature uses to spectacular advantage, has not been fully exploited in synthetic copolymers. To investigate the effect of sequence and stereosequence on the physical properties of copolymers, a family of complex isotactic, syndiotactic, and atactic repeating sequence poly(lactic-co-glycolic acid) copolymers (RSC PLGAs) were prepared and their NMR and thermal behavior was studied. The unique suitability of polymers prepared from the bioassimilable lactic and glycolic acid monomers for biomedical applications makes them ideal candidates for this type of sequence engineering. Polymers with repeating units of LG, GLG and LLG (L = lactic, G = glycolic) with controlled and varied tacticities were synthesized by assembly of sequence-specific, stereopure dimeric, trimeric, and hexameric segmer units. Specifically labeled deuterated lactic and glycolic acid segmers were likewise prepared and polymerized. Molecular weights for the copolymers were in the range Mn = 12-40 kDa by size exclusion chromatography in THF. Although the effects of sequence-influenced solution conformation were visible in all resonances of the 1H and 13C NMR spectra, the diastereotopic methylene resonances in the 1H NMR (CDCl3) for the glycolic units of the copolymers proved most sensitive. An octad level of resolution, which corresponds to an astounding 31-atom distance between the most separated stereocenters, was observed in some mixed sequence polymers. Importantly, the level of sensitivity of a particular NMR resonance to small differences in sequence was found to depend on the sequence itself. Thermal properties were also correlated with sequence.
STEREOSELECTIVE SYNTHESIS OF 1-[6-ETHYL-1,2-DIHYDROXY-PROPYL)-PYRIDIN-3-YL]-3-[2-(4-METHYL-PIPERAZIN-1-YL)-BENZYL]-PYRROLIDIN-2-ONE
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Page/Page column 14; 34, (2008/12/06)
The present invention is related to the stereospecific preparation of 1-[6-(1- ethyl-1,2-dihydroxy-propyl)-pyridin-3-yl]-3-[2-(4-methyl-piperazin-1-yl)-benzyl]- pyrrolidin-2-one, and the intermediates thereof. Another aspect of the invention relates to 1-[6-(1 -ethyl- 1,2-dihydroxy-propyl)-pyridin-3-yl]-3-[2-(4-methyl-piperazin-1- yl)-benzyl]-pyrrolidin-2-one, wherein the carbon atoms having the 1,2-dihydroxy substituents are any of the four diastereomers selected from (R,R), (R,S), (S,R), and (S, S), wherein the carbon three of the pyrrolidin-2-one is (R) or (S), pharmaceutically acceptable salts thereof, solvates thereof, pharmaceutical compositions containing them, and methods using them for in treating or preventing depression, anxiety, obsessive compulsive disorder (OCD) and other disorders for which a 5-HT1 agonist or antagonist is indicated.
