scholarly journals Bio-inspired synthetic approaches: from hierarchical, hybrid supramolecular assemblies to CaCO3-based microspheres

2017 ◽  
Vol 46 (19) ◽  
pp. 6456-6463 ◽  
Author(s):  
Bartosz Marzec ◽  
Lei Zhang ◽  
Nianyong Zhu ◽  
Wolfgang Schmitt

A bio-inspired synthetic approach to Ca(ii)-based coordination assemblies is reported; the supramolecular system was used as habit modifier for CaCO3 materials.

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5938
Author(s):  
Jaehoon Sim ◽  
Eunbin Jang ◽  
Hyun Jin Kim ◽  
Hongjun Jeon

Pladienolides, an emerging class of naturally occurring spliceosome modulators, exhibit interesting structural features, such as highly substituted 12-membered macrocycles and epoxide-containing diene side chains. The potential of pladienolides as anti-cancer agents is confirmed by H3B-8800, a synthetic analog of this natural product class, which is currently under Phase I clinical trials. Since its isolation in 2004 and the first total synthesis in 2007, a dozen total syntheses and synthetic approaches toward the pladienolide class have been reported to date. This review focuses on the eight completed total syntheses of naturally occurring pladienolides or their synthetic analogs, in addition to a synthetic approach to the main framework of the natural product.


Author(s):  
Günther Thiele ◽  
Silke Santner ◽  
Stefanie Dehnen

AbstractThe formation and transformation of crystalline chalcogenido metalates in ionic liquids as solvents is discussed as a new synthetic approach for the generation of novel materials. A comparison to conventional solvothermal reactions, classical high-temperature syntheses and chemical solution based approaches in common is discussed.


Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6306
Author(s):  
Giacomo Biagiotti ◽  
Ilaria Perini ◽  
Barbara Richichi ◽  
Stefano Cicchi

The success of the rational bottom-up approach to nanostructured carbon materials and the discovery of the importance of their doping with heteroatoms puts under the spotlight all synthetic organic approaches to polycyclic aromatic hydrocarbons. The construction of atomically precise heteroatom doped nanographenes has evidenced the importance of controlling its geometry and the position of the doping heteroatoms, since these parameters influence their chemical–physical properties and their applications. The growing interest towards this research topic is testified by the large number of works published in this area, which have transformed a once “fundamental research” into applied research at the cutting edge of technology. This review analyzes the most recent synthetic approaches to this class of compounds.


1986 ◽  
Vol 64 (3) ◽  
pp. 449-456 ◽  
Author(s):  
Arthur E. Martell ◽  
Ramunas J. Motekaitis ◽  
Eric T. Clarke ◽  
J. J. Harrison

Two synthetic approaches for the synthesis of N,N′-di(2-hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED) and derivatives are reported. The first involves conversion of N,N′-di(2-hydroxybenzyl)ethylenediamine to the diamide HBEDDA via reaction with formaldehyde and HCN followed by hydrolysis. Analysis of the species distribution curves of the Cu(II) chelates of N,N′-di(2-hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED) and its diamide, HBEDDA, and of the nature of the coordination in each complex species formed, suggest the selection of the reaction conditions most favorable for the Cu(II)-catalyzed hydrolysis of HBEDDA to HBED. The rate of conversion was found to be low, and the reasons for these findings are described. Iron(III) catalysis of the conversion of HBEDDA to HBED was found to be rapid and complete with a pseudo-first-order rate constant of 3.1 × 10−3 s−1 at 25.0 °C. The results provide the final step of a new method for the synthesis of HBED. The second synthetic approach involves reaction of N,N′-ethylenediamine-diacetic acid (EDDA) with substituted phenols and formaldehyde. These approaches appear to be general for the synthesis of HBED and derivatives.


Catalysts ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 362 ◽  
Author(s):  
Stefano Serra ◽  
Davide De Simeis

The enantiomeric forms of the alcohol (2,6,6-trimethyltetrahydro-2H-pyran-2-yl)methanol are potential chiral building blocks for the stereoselective synthesis of different natural terpenes. Here, we describe their preparation by means of two different synthetic approaches. The first is based on the stereospecific (+)-10-camphorsulfonic acid (CSA)-catalyzed cyclization of (R)- and (S)-2-methyl-5-(2-methyloxiran-2-yl)pentan-2-ol, which were in turn synthesized from (R)- and (S)-linalool, respectively. The latter monoterpenes are easily available from the chiral pool, with different optical purity. As our synthesis makes use of the intermediate 2,6-dimethyloct-7-ene-2,6-diol, whose enantiopurity can be improved through fractional crystallization, we obtained (2,6,6-trimethyltetrahydro-2H-pyran-2-yl)methanol enantiomers in an almost enantiopure form. The second synthetic approach is based on the lipase-mediated resolution of the aforementioned tetrahydropyranyl alcohol, which was prepared in racemic form starting from the industrial intermediate, dehydrolinalool. In this work, we report a large-scale resolution procedure that exploits the opposite enantioselectivity of Novozym® 435 lipase and lipase AK in the acetylation reaction of (2,6,6-trimethyltetrahydro-2H-pyran-2-yl)methanol. The two enantiomeric forms of the latter alcohol were employed for the first stereoselective synthesis of both enantiomers of the flavor, linaloyl oxide (2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran).


2007 ◽  
Vol 3 (S248) ◽  
pp. 443-449 ◽  
Author(s):  
A. C. Robin ◽  
C. Reylé ◽  
D. Marshall

AbstractRecent optical and near-infrared surveys have considerably improved our knowledge of galactic structure and galactic evolution. Two ways can be used to infer this knowledge from datasets: either inversing the data to get parameters describing the Galaxy, or using a synthetic approaches to test scenarios of formation and theoretical models for star and galaxy formation and evolution, both approaches being complementary. Using the synthetic approach the Besancon Galaxy model allows to test scenarios for the structure and evolution of the Galaxy by comparing simulations with the survey data. Examples are given using the 2MASS survey. Future uses of astrometric survey data are shown to be able to efficiently constrain the kinematics and dynamics of the Galaxy.


2017 ◽  
Vol 7 (2) ◽  
pp. 60-75 ◽  
Author(s):  
KOK TONG ONG ◽  
ZHI-QIANG LIU ◽  
MENG GUAN TAY

Pyrazine is a kind of natural product which can be found in plants, animals, insects, marine organisms andmicroorganisms. The main function of pyrazine in living organisms is used as flavor of the raw foods. Pyrazine and its derivatives were also produced in industries mainly for fragrance, flavor and pharmaceutical applications. This review describes the historical development of pyrazine including the discovery and synthesis, to the recent synthetic approach of pyrazinium. In general, six synthetic approaches namely condensation reaction, ring closure, metal catalysis, green reaction, Maillard reaction and acid catalyst on N-substitution have been reviewed in this paper. The first five approaches are mainly aimed for the substitution at 2, 3, 5 and 6 positions in pyrazine ring, whereas the last approach is specifically for 1 and 4 positions in pyrazine. Keywords: Diazine, pyrazine, and Maillard reaction


2020 ◽  
Vol 1 (3) ◽  
pp. 209-237
Author(s):  
Ashlyn D. Smith ◽  
Andrew G. Tennyson ◽  
Rhett C. Smith

This paper is review with 119 references. Approaches to supplant currently used plastics with materials made from more sustainably-sourced monomers is one of the great contemporary challenges in sustainable chemistry. Fatty acids are attractive candidates as polymer precursors because they can be affordably produced on all inhabited continents, and they are also abundant as underutilized by-products of other industries. In surveying the array of synthetic approaches to convert fatty acids into polymers, those routes that produce organosulfur polymers stand out as being especially attractive from a sustainability standpoint. The first well-explored synthetic approach to fatty acid-derived organosulfur polymers employs the thiol-ene click reaction or the closely-related thiol-yne variation. This approach is high-yielding under mild conditions with up to 100% atom economy and high functional group tolerance. More recently, inverse vulcanization has been employed to access high sulfur-content polymers by the reaction of fatty acid-derived olefins with elemental sulfur. This approach is attractive not only because it is theoretically 100% atom economical but also because elemental sulfur is itself an underutilized by-product of fossil fuel refining. The thiol-ene, inverse vulcanization, and mechanistically-related thiol-yne and classic vulcanization are therefore discussed as promising routes to access polymers and composites from fatty acid-derived precursors.


2020 ◽  
Vol 16 ◽  
pp. 2322-2331
Author(s):  
Ekaterina E Stepanova ◽  
Maksim V Dmitriev ◽  
Andrey N Maslivets

Two synthetic approaches to enaminones fused to 1,4-benzothiazin-2-one moiety, which can be interesting in studies on biological activity, chemosensors, and fluorescence, were developed via the reaction of furan-2,3-diones or acylpyruvic acids in the presence of carbodiimides with o-aminothiophenols. The target enaminones were formed together with pharmaceutically interesting 2-hydroxy-2H-1,4-benzothiazin-3(4H)-ones. A selective synthetic approach to 2-hydroxy-2H-1,4-benzothiazin-3(4H)-ones was developed via the solvent-switchable reaction of furan-2,3-diones with o-aminothiophenol. Preliminary biological assays (antimicrobial, acute toxicity) of the new compounds were carried out.


2015 ◽  
Vol 71 (12) ◽  
pp. 1062-1068 ◽  
Author(s):  
Lina M. Acosta ◽  
Jorge Jurado ◽  
Alirio Palma ◽  
Justo Cobo ◽  
Christopher Glidewell

Dibenz[b,f]azepine (DBA) is a privileged 6-7-6 tricyclic ring system of importance in both organic and medicinal chemistry. Benzo[b]pyrimido[5,4-f]azepines (BPAs), which also contain a privileged 6-7-6 ring system, are less well investigated, probably because of a lack of straightforward and versatile methods for their synthesis. A simple and versatile synthetic approach to BPAs based on intramolecular Friedel–Crafts alkylation has been developed. A group of closely-related benzo[b]pyrimido[5,4-f]azepine derivatives, namely (6RS)-4-chloro-6,11-dimethyl-6,11-dihydro-5H-benzo[b]pyrimido[5,4-f]azepine, C14H14ClN3, (I), (6RS)-4-chloro-8-hydroxy-6,11-dimethyl-6,11-dihydro-5H-benzo[b]pyrimido[5,4-f]azepine, C14H14ClN3O, (II), (6RS)-4-<!?tlsb=-0.14pt>chloro-8-methoxy-6,11-dimethyl-6,11-dihydro-5H-benzo[b]pyrimido[5,4-f]azepine, C15H16ClN3O, (III), and (6RS)-4-chloro-8-methoxy-6,11-dimethyl-2-phenyl-6,11-dihydro-5H-benzo[b]pyrimido[5,4-f]azepine, C21H20ClN3O, (IV), has been prepared and their structures compared with the recently published structure [Acosta-Quinteroet al.(2015).Eur. J. Org. Chem.pp. 5360–5369] of (6RS)-4-chloro-2,6,8,11-tetramethyl-6,11-dihydro-5H-benzo[b]pyrimido[5,4-f]azepine, (V). All five compounds crystallize as racemic mixtures and they have very similar molecular conformations, with the azepine ring adopting a boat-type conformation in each case, although the orientation of the methoxy substituent in each of (III) and (IV) is different. The supramolecular assemblies in (II) and (IV) depend upon hydrogen bonds of the O—H...N and C—H...π(arene) types, respectively, those in (I) and (V) depend upon π–π stacking interactions involving pairs of pyrimidine rings, and that in (III) depends upon a π–π stacking interaction involving pairs of phenyl rings. Short C—Cl...π(pyrimidine) contacts are present in (I), (II) and (IV) but not in (III) or (V).


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