
Antonio L. Llamas-Saiz- PhD
- Head of Department at University of Santiago de Compostela
Antonio L. Llamas-Saiz
- PhD
- Head of Department at University of Santiago de Compostela
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194
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Introduction
Current institution
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October 1999 - present
September 1989 - September 1999
March 1994 - April 1996
Education
September 1984 - January 1993
Publications
Publications (194)
By deprotonating Btp-derived ligands, precise control over counterions in the outer-coordination sphere is achieved in both neutral and charged anisotropic Co II complexes exhibiting field-induced single-ion magnetism.
The biological and technological importance of anion-mediated processes has made the development of improved methods for the selective recognition of anions one of the most relevant research topics today. The hydration sphere of anions plays an important role in the functions performed by anions by forming a variety of cluster complexes. Here we de...
Zeolites, well-known by their high selectivities in catalytic and separation processes due to their porous nature, play a crucial role in various applications. One significant long-term objective is the synthesis of enantiopure zeolites, potentially enabling enantioselective processes. Earlier attempts result in partial success, yielding some enant...
The biological and technological importance of anion-mediated processes has made the development of improved methods for the selective recognition of anions one of the most relevant research topics today. The hydration sphere of anions plays an important role in the functions performed by anions by forming a variety of cluster complexes. Here we de...
Nowadays around 46% of food production around the world requires refrigeration, which is generally provided either by active vapour-compression (based on refrigerants with liquid-gas transitions) or passive cold-storage (based on...
In this work, we report a new halometallate [(CH₃)₃S][FeCl4] with plastic crystal behaviour as a new material for multi-energy storage. This material undergoes a first-order solid-solid plastic crystal phase transition near room temperature with a relatively large latent heat (~40 kJ kg-1) and an operational temperature for storing and releasing th...
In this work, we report a new halometallate [(CH3)3S][FeCl4] with plastic crystal behaviour as a new material for multi-energy storage. This material undergoes a first-order solid-solid plastic crystal phase transition near room temperature with a relatively large latent heat (~40 kJ kg-1) and an operational temperature for storing and releasing th...
Self-assembled ionic liquid crystals are anisotropic ionic conductors, with potential applications in areas as important as solar cells, battery electrolytes and catalysis. However, many of these applications are still limited by the lack of precise control over the variety of phases that can be formed (nematic, smectic, or semi/fully crystalline),...
We have been able to prepare two new lead halides with formula DMAPbX3 (where DMA is dimethylammonium and X is Cl- or Br-), which display a 4H-hexagonal perovskite polytype, an unusual crystal structure in hybrid organic-inorganic perovskites. Both compounds experience a first order phase transition, the chloride at ≈320 K and the bromide at ≈250 K...
The GAIIG sequence, common to the amyloid beta peptide (residues 29‐33) and to the HIV gp 120 (residues 24‐28 in a typical V3 loop) self‐assembles into amyloid fibrils, as suggested by theory and the experiments presented here. The longer YATGAIIGNII sequence from the V3 loop also self‐assembles into amyloid fibrils, of which the first three and th...
We have prepared two new lead halides with the novel general formula of DMA7Pb4X15(DMA = [(CH3)2NH2]+and X = Cl-or Br-) by using an easy route under mild conditions at room temperature. These compounds exhibit an unprecedented crystal structure, are formed by layers of distorted [PbX6] octahedra, which share corners and faces, and contain intercala...
In this work, we focus on [(CH3)2NH2]PbI3, a member of the [AmineH]PbI3 series of hybrid organic-inorganic compounds, reporting a very easy mechanosynthesis route for its preparation at room temperature. We report that this [(CH3)2NH2]PbI3 compound with 2H-perovskite structure experiences a first-order transition at ?250 K from hexagonal symmetry P...
A convenient synthesis of an octacyclic compound containing an iodo and a trimethylsilyl group in vicinal double-bridgehead positions, as a possible precursor of a pyramidalized alkene, is described. The key step of the synthesis consists of a double nucleophilic substitution of two neopentyl-type iodides by cyclopentadienide anions followed by two...
We report here the straightforward synthesis of some dimeric transition metal complexes of three Schiff base ligands, which were obtained by condensation of 2-tosylaminomethylaniline with 2,3-dihydroxybenzaldehyde (H2L1), 2,4-dihydroxybenzaldehyde (H2L2) and 4-formyl-3-hydroxybenzoic acid (H2L3), respectively. Both ligands and complexes were charac...
Bacteriophage T5, a Siphovirus belonging to the order Caudovirales, has a flexible, three-fold symmetric tail, to which three L-shaped fibres are attached. These fibres recognize oligo-mannose units on the bacterial cell surface prior to infection and are composed of homotrimers of the pb1 protein. Pb1 has 1396 amino acids, of which the carboxy-ter...
Purely organic shape-persistent chiral cages are designed through the use of rigid chiral axes. Covalent dimerization of a tripodal fragment bearing chiral allenes forms a molecular twisted prism with loop-like lateral edges presenting 10-fold chiroptical amplification compared to its isolated building blocks. The expected geometry of covalent orga...
In this work we explore the overall structural behaviour of the [(CH3)2NH2][Mn(HCOO)3] multiferroic compound across the temperature range where its ferroelectric transition takes place by means of calorimetry, thermal expansion measurements and variable temperature powder and single crystal X-ray diffraction. The results clearly prove the presence...
A chiral bidentate inclusion complex has been formed by halogen-bond interaction between the pyridyl moieties of a pyridoallenoacetylenic host and octafluorodiiodobutane. X-ray crystallography showed that the guest adopts a chiral conformation inside the molecular channels formed by stacking of the host units. A 10 ppm shielding of the (15)N NMR re...
The structural changes caused by the substitution of the aromatic moiety in (2S)-2-benzyl-3-dehydroquinic acids and its epimers in C2 by electron-withdrawing or electron-donating groups in type II dehydroquinase enzyme from M. tuberculosis and H. pylori has been investigated by structural and computational studies. Both compounds are reversible com...
About the Cover:
The three faces of the type II dehydroquinase enzyme. The cover depicts how 2-benzyl-3-dehydroquinic acids inactivate this essential enzyme in bacteria by causing a significant conformational change in the flexible loop, which is essential for its function. These changes (closed and semi-closed) depend on the substitution of the a...
X-ray crystallography is a powerful technique to determine the three-dimensional structure of any kind of molecule at atomic resolution, including that of biological macromolecules. This chapter covers the main concepts to understand the basic theory behind an X-ray diffraction crystal structure determination. The chapter outlines, from a practical...
New 2,6-disubstituted pyrido-allenophanes with locked rotation of aromatic spacers were designed and synthesized. The synthesis was accomplished by Pd-catalyzed C(sp(2) )-C(sp) Sonogashira cross-coupling reaction between 1,3-diethynylallene (DEA) and 2,6-dibromopyridine followed by an intermolecular ring closure. Because racemic DEA was employed, p...
Enoyl-acyl carrier protein reductase (ENR; the product of the fabI gene) is an important enzyme that is involved in the type II fatty-acid-synthesis pathway of bacteria, plants, apicomplexan protozoa and mitochondria. Harmful pathogens such as Mycobacterium tuberculosis and Plasmodium falciparum use the type II fatty-acid-synthesis system, but not...
The synthesis of high-affinity reversible competitive inhibitors of Mycobacterium tuberculosis type II dehydroquinase, an essential enzyme in Mycobacterium tuberculosis bacteria, is reported. The inhibitors reported here are mimics of the enol intermediate and the effect of substitution on C2 was studied. The crystal structures of Mycobacterium tub...
Monobenzylated sugar amino acids (SAAs) that differ in ether ring size (containing an oxetane, furanoid, and pyranoid ring) were synthesized and incorporated in one of the β-turn regions of the cyclo-decapeptide gramicidin S (GS). CD, NMR spectroscopy, modeling, and X-ray diffraction reveal that the ring size of the incorporated SAA moieties determ...
The influence of replacing the d-phenylalanine residue with substituted and unsubstituted azoles on the structure and biological activity of the antibiotic gramicidin S was investigated against a representative panel of Gram-positive and Gram-negative bacteria strains. Substituted triazole derivatives, obtained using a convergent synthetic strategy...
Restriction is good for inhibition! Tetrahydrobenzothiophene‐derived rigid mimics of the type II dehydroquinase (DHQ2)‐catalyzed reaction intermediate are reported. These derivatives fix the interaction with the tyrosine, the base that initiates the enzymatic reaction, in an inappropriate orientation for catalysis. Two competitive inhibitors in the...
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Bacteriophages are the most numerous organisms in the biosphere. In spite of their biological significance and the spectrum of potential applications, little high-resolution structural detail is available on their receptor-binding fibers. Here we present the crystal structure of the receptor-binding tip of the bacteriophage T4 long tail fiber, whic...
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
The cyclic cationic antimicrobial peptide gramicidin S (GS) is an effective topical antibacterial agent that is toxic for human red blood cells (hemolysis). Herein, we present a series of amphiphilic derivatives of GS with either two or four positive charges and characteristics ranging between very polar and very hydrophobic. Screening of this seri...
The binding mode of several substrate analogues, (2R)-2-benzyl-3-dehydroquinic acids 4, which are potent reversible competitive inhibitors of type II dehydroquinase (DHQ2), the third enzyme of the shikimic acid pathway, has been investigated by structural and computational studies. The crystal structures of Mycobacterium tuberculosis and Helicobact...
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Results of the crystal structure analysis of three 1-dimethylamino-8-triphenylphosphoranylideneammonionaphthalene salts are described. The ‘extra proton’ has been found to bind to the nitrogen atom of the iminophosphorane group, being engaged in a strong intramolecular contact [N N = 2.519(3), 2.543(4), 2.571(6)Å; N–H N = 154(6), 155(6) and 147(6)°...
The cyclic decapeptide gramicidin S (GS) was used as a model for the evaluation of four turn mimetics. For this purpose, one of the D-Phe-Pro two-residue turn motifs in the rigid cyclic beta-hairpin structure of GS was replaced with morpholine amino acids (MAA 2-5), differing in stereochemistry and length of the side-chain. The conformational prope...
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Adenovirus isolate NADC-1, a strain of porcine adenovirus type 4, has a fiber containing an N-terminal virus attachment region,
shaft and head domains, and a C-terminal galectin domain connected to the head by an RGD-containing sequence. The crystal
structure of the head domain is similar to previously solved adenovirus fiber head domains, but spec...
The porcine adenovirus NADC-1 isolate, a strain of porcine adenovirus type 4, has a fibre with an atypical architecture. In addition to a classical virus attachment region, shaft and head domains, it contains an additional galectin like domain C-terminal to the head domain and connected to the head domain by a long RGD-containing loop. The galectin...
The natural product Gramicidin S is a promising scaffold for novel oligopeptide-based bisphosphine ligands, combining the advantageous rigid chiral backbone with the close proximity of phosphine substituents. The required unnatural, phosphine-containing, amino acid building blocks were synthesized by means of a novel protocol that involves the enan...
The synthesis of new analogues of the cationic antimicrobial peptide gramicidin S, having a modified D-phenylalanine residue, their antibacterial properties against several gram positive and negative strains, as well as their hemolytic activity is reported.
Avian reovirus fibre, a homo-trimer of the sigmaC protein, is a minor component of the avian reovirus outer capsid. It is anchored via a short N-terminal sequence to the inner capsid lambdaC pentamer, and its protruding globular C-terminal domain is responsible for primary host cell attachment. We have previously solved the structure of a receptor-...
Avian reovirus, an important avian pathogen, expresses eight structural and four nonstructural proteins. The structural σA
protein is a major component of the inner capsid, clamping together λA building blocks. σA has also been implicated in the
resistance of avian reovirus to the antiviral action of interferon by strongly binding double-stranded R...
A new Salmonella enterica phage, Det7, was isolated from sewage and shown by electron microscopy to belong to the Myoviridae morphogroup of bacteriophages. Det7 contains a 75-kDa protein with 50% overall sequence identity to the tail spike endorhamnosidase of podovirus P22. Adsorption of myoviruses to their bacterial hosts is normally mediated by l...
Avian adenovirus CELO (chicken embryo lethal orphan virus, fowl adenovirus type 1) incorporates two different homotrimeric fiber proteins extending from the same penton base: a long fiber (designated fiber 1) and a short fiber (designated fiber 2). The short fibers extend straight outwards from the viral vertices, whilst the long fibers emerge at a...
The first crystal structures of HgII complexes of EDTA and PDTA tetra-amides are reported. Reaction of EDTA and PDTA tetra-amides (L1 and L2) and tetramethylamides (L3 and L4) with HgCl2 in water/ethanol/acetone produced complexes of formula [Hg(L1)Cl][HgCl4]0.5·0.5H2O, (1), [Hg(L2)Cl]2[HgCl4]·6H2O, (2), [Hg3(L3)2Cl4][HgCl3]2·2H2O, (3), [Hg(L3)Cl]2...
The pyridyl and benzene rings in the title compound, C25H26N4 center dot 2H(2)O, show significant deviation from coplanarity due to a twist in the molecule, and this is reflected in the C-N( H)-C-C torsion angles of -82.8 (3) and 70.8 (3)degrees. The supramolecular architecture is effected by O-H center dot center dot center dot O quadrilaterals, o...
The pyridyl and benzene rings in the title compound, C25H26N4·2H2O, show significant deviation from coplanarity due to a twist in the molecule, and this is reflected in the C—N(H)—C—C torsion angles of −82.8 (3) and 70.8 (3)°. The supramolecular architecture is effected by O—H⋯O quadrilaterals, one-dimensional N—H⋯O chains, two-dimensional netwo...
The avian reovirus protein sigmaA plays a dual role: it is a structural protein forming part of the transcriptionally active core, but it has also been implicated in the resistance of the virus to interferon by strongly binding double-stranded RNA and thus inhibiting the double-stranded RNA-dependent protein kinase. The sigmaA protein has been crys...
Gramicidin S is a nonribosomally synthesized cyclic decapeptide antibiotic with twofold symmetry (Val-Orn-Leu-d-Phe-Pro)2; a natural source is Bacillus brevis. Gramicidin S is active against Gram-positive and some Gram-negative bacteria. However, its haemolytic toxicity in humans limits its use as an antibiotic to certain topical applications. Syn...
The acetylacetonate complexes [Ni(2)L(1)(acac)(MeOH)] x H(2)O, 1 x H(2)O and [Ni(2)L(3)(acac)(MeOH)] x 1.5H(2)O, 2 x 1.5H(2)O (H(3)L(1) = (2-(2-hydroxyphenyl)-1,3-bis[4-(2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-imidazolidine and H(3)L(3) = (2-(5-bromo-2-hydroxyphenyl)-1,3-bis[4-(5-bromo-2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-imidazolidine) were prepare...
An attractive target: Multiple porphyrin systems (see picture for example) are at the center of many synthetic efforts, and efficient strategies for preparing valuable building blocks for these polycycles are much sought after. Herein such a strategy for the synthesis of [1,2,3]triazolo[4,5-b]-porphyrin building blocks is presented. (Figure Present...
Ein attraktives Ziel: An Synthesen von Multiporphyrin-Systemen (im Bild ist ein Beispiel gezeigt) wird intensiv gearbeitet, und dabei sind vor allem effiziente Strategien zur Herstellung geeigneter Bausteine für diese Polycyclen gefragt. Hier wird eine solche Strategie für die Synthese von [1,2,3]Triazolo[4,5-b]porphyrin-Bausteinen vorgestellt.
Avian adenovirus CELO contains two different fibres: fibre 1, the long fibre, and fibre 2, the short fibre. The short fibre is responsible for binding to an unknown avian receptor and is essential for infection of birds. The long fibre is not essential, but is known to bind the coxsackievirus and adenovirus receptor protein. Both trimeric fibres ar...
Avian reovirus fibre, a homo-trimer of the sigmaC protein, is responsible for primary host cell attachment. The protein expressed in bacteria forms elongated fibres comprised of a carboxy-terminal globular head domain and a slender shaft, and partial proteolysis yielded a carboxy-terminal protease-stable domain that was amenable to crystallisation....
Avian reovirus fibre, a homotrimer of the sigmaC protein, is responsible for primary host-cell attachment. Using the protease trypsin, a C-terminal sigmaC fragment containing amino acids 156-326 has been generated which was subsequently purified and crystallized. Two different crystal forms were obtained, one grown in the absence of divalent cation...
Two strains of the parvovirus minute virus of mice (MVM), the immunosuppressive (MVMi) and the prototype (MVMp) strains, display
disparate in vitro tropism and in vivo pathogenicity. We report the crystal structures of MVMp virus-like particles (MVMpb) and native wild-type (wt) empty capsids (MVMpe), determined and refined to 3.25 and 3.75 Å resolu...
The copper(II) complex Cu(2)L(OMe)(H(2)O)(3), [middle dot]3H(2)O [H(3)L = 2-(2-hydroxyphenyl)-1,3-bis[4-(2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-imidazolidine] was obtained and recrystallised in methanol to yield crystals of [[Cu(2)L(OMe)]](2).2.5MeOH.4H(2)O, 1.2.5MeOH.4H(2)O. Its single X-ray study shows that it contains two crystallographically dif...
Sugar amino acids (SAAs) are useful building blocks for the design of peptidomimetics and peptide scaffolds. The three-dimensional structures of cyclic hybrid molecules containing the furanoid epsilon-SAA III and several amino acids were elucidated to study the preferred conformation of such an epsilon-SAA and its conformational influence on the ba...
The electrochemical reaction of zinc and 2-(2-hydroxyphenyl)-1,3-bis[4-(2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-imidazolidine (H3L1) in acetonitrile in air yields the tetranuclear zinc complex [(Zn2L)2(CO3)]·4H2O, which crystallises with different solvent molecules in two different systems: [(Zn2L)2(CO3)]·4H2O·2CH3CN 1a
(monoclinic, Pn) and [(Zn2L)2(...
The electrochemical reaction of zinc and 2-(2-hydroxyphenyl)-1,3-bis[4-(2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-i midazolidine (H3L1) in acetonitrile in air yields the tetranuclear zinc complex [(Zn2L)(2)(CO3)].4H(2)O, which crystallises with different solvent molecules in two different systems: [(Zn2L)(2)(CO3)].4H(2)O.2CH(3)CN 1a (monoclinic, Pn) an...
Sodium in dry methanol reduces 2-cyanopyridine in the presence of N(4)-dimethylthiosemicarbazide to produce 2-pyridyl-formamide N(4)-dimethylthiosemicarbazone, HAm4DM. Complexes with zinc(II) and cadmium(II) of formulae [M(Am4DM)(OAc)]2 and [M(HAm4DM)X2] (M = Zn or Cd, X = Cl, Br or I) have been prepared and characterized by spectroscopic technique...
We report the ab initio study of twenty-four azolides derived from pyrrole, imidazole, pyrazole, both triazoles, tetrazole, pentazole, indole and carbazole bearing at the nitrogen atom the groups COMe, CHO, COCF3 and CO2Me. Theoretical values (isomerism, barriers, dipole moments, C=O stretching) are compared with experimental ones, when available,...
An electrochemical synthesis yielded powdery [Zn-2(L)(H2O)](n) [H4L = N,N'-bis(3-hydroxysalicylidene)-1,4- diaminobutane] and crystals of [Zn-8(L)(4)(H2O)(3)]. H2O. 0.25MeCN, whose X-ray crystal structure shows an unusual pseudo-tetrahedral Zn8O13 core assembled by thirteen mu-phenoxo bridges, where Zn(II) ions are pentaco-ordinated.
The VP-2 major capsid protein of the prototype strain of the parvovirus minute virus of mice (MVMp) was expressed, using a baculovirus vector, in Sf9 insect cells. Immunogold electron microscopy of infected Sf9 cells showed VP-2 localized in the nucleus and cytoplasm as is observed in mammalian cells during natural infections. The VP-2 subunits sel...
The crystal and molecular structure of two salts, I and III, and one molecular complex, II, formed by combining 1,1'-binaphthyl-2,2'-dicarboxylic acid (BNDA) with pyrazole (3) and 3,5-dimethylpyrazole (4) has been determined by X-ray crystallography. The most striking feature is the spontaneous resolution of the racemic BNDA host by co-crystallizat...
3-(2-Benyloxy-6-hydroxyphenyl)-5-styrylpyrazoles 7a-e were prepared from the reaction of 2-styrylchromones and hydrazine hydrate. 3-(2-Benzyloxy-6-hydroxyphenyl)-5-(2-phenylethyl)-pyrazoles pyrazoles 8a,d,e and 3-(2-benzyloxy-beta,6-dihydroxystyryl)-5-aryl-2-pyrazolines 9a-e were also obtained as by-products. The crystal and molecular structure of...
The crystal structure of 3(5)-phenyl-4-bromo-5(3)-methylpyrazole, 3, has been determined by X-ray crystallography. Both tautomers are present simultaneously in the crystals forming cyclic tetramers. The proton disorder, determined by the crystallographic methods, has been established to be dynamic using solid state C-13 CPMAS NMR spectroscopy. This...
New chiral host compounds based on mandelic acid derivatives having methyl (6a, b and 8a, b) or bromo substituents (7a, b) attached to the phenyl ring of mandelic acid and involving additional aromatic groups were synthesized. The inclusion properties of both the racemic and the optically resolved host species are reported, including solvent co-cry...