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Showing papers on "Substituent published in 1992"


Journal ArticleDOI
TL;DR: In this article, the 3-hexylthiophene 2,5-diyl (3-hexylonthiophenes) (HT-PHT) was synthesized with a head-to-tail regioregularity of 91% and an alternative synthesis with almost equal distribution of different linkages in the polymer chain.
Abstract: Recent research on poly(alkylthiophenes) (PAT) has concentrated on the regularity and structure of the polymer chain of PAT. The 3-alkyl substituent in a thiophene ring can be incorporated into a polymer chain with two different regioregularities: head-to-tail (HT) and head-to-head (HH). Head-to-head linkages can cause defects in the polymer chain. The highest regioregularity reported to date for HT-PAT is 91% (usually 50-60% HT regioregularity). The authors report herein a new and facile synthesis which leads to the first completely head-to-tail regioregular poly(3-hexylthiophene 2,5-diyl) (HT-PHT) and an alternative synthesis which yields an unusual regiorandom PHT with almost equal distribution of different linkages in the polymer chain. Both polymers have been characterized by NMR, IR, elemental analysis, GPC (gel-permeation chromatography), and UV-vis. 11 refs., 2 figs., 1 tab.

485 citations


Patent
23 Oct 1992
TL;DR: Linked nucleosides having at least one functionalized nucleoside that bears a substituent such as a steroid molecule, a reporter molecule, non-aromatic lipophilic molecule, an enzyme, a peptide, a protein, a water soluble vitamin, a lipid soluble vitamin this article, an RNA cleaving complex, a metal chelator, a porphyrin, an alkylator, pyrene, a hybrid photonuclease/intercalator, or an aryl azide photo-crosslinking agent exhibit increased cellular uptake and other properties
Abstract: Linked nucleosides having at least one functionalized nucleoside that bears a substituent such as a steroid molecule, a reporter molecule, a non-aromatic lipophilic molecule, a reporter enzyme, a peptide, a protein, a water soluble vitamin, a lipid soluble vitamin, an RNA cleaving complex, a metal chelator, a porphyrin, an alkylator, a pyrene, a hybrid photonuclease/intercalator, or an aryl azide photo-crosslinking agent exhibit increased cellular uptake and other properties. The substituent can be attached at the 2′-position of the functionalized nucleoside via a linking group. If at least a portion of the remaining liked nucleosides are 2′-deoxy-2′-fluoro, 2′-O-methoxy, 2′-O-ethoxy, 2′-O-propoxy, 2′-O-aminoalkoxy or 2′-O-allyloxy nucleosides, the substituent can be attached via a linking group at any of the 3′ or the 5′ positions of the nucleoside or on the heterocyclic base of the nucleoside or on the inter-nucleotide linkage linking the nucleoside to an adjacent nucleoside.

418 citations


Journal ArticleDOI
TL;DR: By tethering a polar hydrophilic group to the P1 or P1' substituent of a Phe-based hydroxyethylene isostere, the antiviral potency of a series of HIV protease inhibitors was improved and the optimum enhancement of anti-HIV activity was observed with the 4-morpholinylethoxy substituents.
Abstract: By tethering of a polar hydrophilic group to the P1 or P1' substituent of a Phe-based hydroxyethylene isostere, the antiviral potency of a series of HIV protease inhibitors was improved. The optimum enhancement of anti-HIV activity was observed with the 4-morpholinylethoxy substituent. The substituent effect is consistent with a model derived from inhibitor docked in the crystal structure of the native enzyme. An X-ray crystal structure of the inhibited enzyme determined to 2.25 A verifies the modeling predictions.

175 citations



Journal ArticleDOI
01 Feb 1992-Langmuir
TL;DR: In this article, the role of phenyl substituent groups in the formation of surface complexes at the surface of titanium dioxide semiconducting ceramic membranes is investigated with cylindrical internal reflection-Fourier transform infrared (CIR-FTIR) spectroscopy.
Abstract: The role of phenyl substituent groups in the formation of surface complexes at the surface of titanium dioxide semiconducting ceramic membranes is investigated with cylindrical internal reflection-Fourier transform infrared (CIR-FTIR) spectroscopy. The CIR-FTIR study presented in this article allows for direct comparison between adsorption mechanisms derived from vibrational spectra at the semiconductor-liquid interface and surface structures influencing aqueous heterogeneous photochemical reactions. Therefore, chemisorption mechanisms we derived for benzoic acid and its substituted compounds could be used for the prediction of their photodegradation behavior. This IR investigation confirms that no adsorption is detectable on the rutile phase of TiO2, thus excluding the role of 5-fold coordinated Ti cations in the adsorption mechanisms. We observed that, for anatase surface, isolated carboxyl groups do not generate a favorable adsorption equilibrium (e.g., benzoic acid). It is proposed that amino and hydroxyl groups substituted in ortho position to a carboxyl group (e.g., salicylic, 3-chlorosalicylic, and anthranilic acids) may lead to a mononuclear bidentate coordination complex with 4-fold coordinated surface titanium cations. The higher adsorption level observed for phthalic acid is interpreted as due to its possibility of adsorbing on a greater number of anatase surface sites, by forming two different surface complexes, involving one or both carboxyl groups. A relationship between change in vibrational spectra of the carboxyl group, for substituted benzoic derivatives, and acidic dissociation constants is presented.

127 citations


Patent
Ronald Swidler1
16 Apr 1992
TL;DR: In this paper, a biodegradable polyester polyester polymer comprising of repeating polymer units of the formula shown is presented, where n = number of repeating polyester units; q = 0 or 1, 0 indicating the absence of the subscripted constituent; when p=0, 1=1; when q = 1, 1.
Abstract: The invention presents a biodegradable polyester polymer comprising ##STR1## wherein: n=number of repeating polymer units of the formula shown; p=0 or 1, 0 indicating the absence of the subscripted constituent; q=0 or 1, 0 indicating the absence of the subscripted constituent; when p=0, 1=1; when p=1, 1=0; R 1 =a divalent organic substituent which can include oxygen, nitrogen or sulfur atoms as part of the polymer backbone; R 2 =a divalent organic substituent which can include oxygen, nitrogen or sulfur atoms as part of the polymer backbone; R 3 and R 4 are each independently hydrogen or an organic substituent or together form a divalent ring which may be optionally substituted; and each R is independently H, alkyl, alkenyl or alkynyl, aryl, aralkyl, cycloalkyl, cycloalkenyl or cycloalkynyl, all optionally substituted with F, Cl, Br, I, CN or NO 2 .

126 citations


Journal ArticleDOI
TL;DR: In this article, the effect of substituents on the properties of acyl derivatives has been examined at the theoretical level and at the MP2/6-31G * theoretical level.
Abstract: The effect of substituents on the properties of acyl derivatives has been examined. Geometry optimizations were carried out at the MP2/6-31G * theoretical level, followed by calculation of energies at the MP3/6-311++G ** level. The energies were studied via isodamic reactions with ethane leading to acetone and a methyl derivative. The calculated energy changes were in good agreement with the available experimental data and showed that groups more electronegative than carbon stabilize a carbonyl group more than methyl, whereas the opposite is true with the more electropositive groups

126 citations


Journal ArticleDOI
TL;DR: In this article, the synthesis of two novel DOTA-like ligands (5a,b) containing a polyhydroxy(benzyloxy)propionamide substituent and their Gd(III) complexes was reported.
Abstract: The synthesis of two novel DOTA-like ligands (5a,b) containing a polyhydroxy(benzyloxy)propionamide substituent and their Gd(III) complexes (6a,b) is reported. Debenzylation by hydrogenolysis of the latter complexes in the presence of Pd/C leads to the corresponding derivatives (7a,b) with a primary alcoholic function. Water proton relaxation rates of aqueous solutions of 6a,b and 7a,b strongly suggest that these complexes contain only one water molecule in their inner coordination sphere, as was previously found for the parent DOTA complex

118 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of substitution position on permselective properties of polyphenylene oxide (PPO) and several of its derivatives was investigated. And the results showed that the methyl-substituted polymers are significantly less permeable, but more selective, than PPO.

112 citations


Patent
05 Jun 1992
TL;DR: In this article, an olefinic compound with hydrogen and carbon monoxide in the presence of a Group VIII metal catalytic catalyst is presented, in the reaction of which there is present a phosphite compound having the formula (I), A¹⁅O-P(OR¹)(ORµ)n (I) wherein R¹ and Rµ are respectively an aromatic hydrocarbon group which may be the same or different and the aromatic hydrocar group has at least a hydrocarbic group on a carbon atom adjacent to an oxygen atom
Abstract: A hydroformylation process for preparing a hydroformylated product by reacting an olefinic compound with hydrogen and carbon monoxide in the presence of a Group VIII metal catalyst, in the reaction of which there is present a phosphite compound having the formula (I), A¹⁅O-P(OR¹)(OR²)]n (I) wherein R¹ and R² are respectively an aromatic hydrocarbon group which may be the same or different and the aromatic hydrocarbon group has at least a hydrocarbon group on a carbon atom adjacent to a carbon atom bonded with an oxygen atom as a substituent; A¹ is an n-valent organic group having an aliphatic hydrocarbon group, a cycloaliphatic hydrocarbon group or an aromatic hydrocarbon group bonded with an adjacent oxygen atom, which may respectively have a substituent; n is an integer of from 2 to 4; and the respective ⁅O-P(OR¹)(OR²)] group may be the same or different.

108 citations


Patent
30 Oct 1992
TL;DR: An anticoagulant agent which comprises, as an active ingredient, an aromatic amidine derivative represented by the following general formula (1) or a salt thereof: ##STR1## wherein the group represented by ##STR2## is a group selected from indolyl, benzofuranyl, benzothienyl, benzimidazolyls, benzoxazolyl and benzothiazolyl; X is a single bond, an oxygen atom, a sulfur atom or a carbonyl group; and Y is a saturated or unsaturated 5- or 6
Abstract: An anticoagulant agent which comprises, as an active ingredient, an aromatic amidine derivative represented by the following general formula (1) or a salt thereof: ##STR1## wherein the group represented by ##STR2## is a group selected from indolyl, benzofuranyl, benzothienyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, naphthyl, tetrahydronaphthyl and indanyl; X is a single bond, an oxygen atom, a sulfur atom or a carbonyl group; and Y is a saturated or unsaturated 5- or 6-membered heterocyclic moiety or cyclic hydrocarbon moiety optionally having a substituent group, an amino group optionally having a substituent group or an aminoalkyl group optionally having a substituent group. The inventive compound has a high anticoagulant capacity based on its excellent FXa inhibition activity.

Journal ArticleDOI
TL;DR: A series of acyclic α-carbomethoxy-α-diazoacetanilides with different N-substituents, 5a-k, was prepared and the rhodium(II) acetate catalyzed reactions studied as discussed by the authors.
Abstract: A series of acyclic α-carbomethoxy-α-diazoacetanilides with different N-substituents, 5a-k, was prepared and the rhodium(II) acetate catalyzed reactions studied. It was found that the rhodium carhenoid reaction with these compounds occurred only at the N-substituent; when the N-substituent is a propargyl group, rhodium carbenoid addition to the triple bond is favored, resulting, ultimately, in the formation of a bicyclic furan derivative 8. With an N-(tert-butyloxycarbonyl)methyl substituent, interception of the rhodium carhenoid by the ester carbonyl oxygen occurred preferentially to give, eventually, 1,4-oxazine derivatives 9 and 9'

Patent
09 Apr 1992
TL;DR: In this article, a method of producing polyolefins having broadened molecular weight distributions and enhanced tensile impact strengths utilizing a silica supported metallocene-alumoxane catalyst system was proposed.
Abstract: A catalyst and method of producing polyolefins having broadened molecular weight distributions and enhanced tensile impact strengths utilizing a silica supported metallocene-alumoxane catalyst system, wherein at least one of the metallocenes has at least one cyclopentadienyl ring being substituted by at least one optionally substituted hydrocarbon substituent having a 2° or 3° carbon atom with which it is covalently bonded to the cyclopentadienyl ring.


Journal ArticleDOI
TL;DR: In this article, Norbornene derivatives containing laterally attached 2,5-bis(4'-n- alkoxybenzoyl OXY) mesogens were polymerized by controlled ring opening metathesis polymerization to provide polymers in high yield with 5-100 repeat units and narrow molecular weight distributions.
Abstract: : Norbornene derivatives containing laterally attached 2,5-bis(4'-n- alkoxybenzoyl OXY) mesogens were polymerized by controlled ring opening metathesis polymerization to provide polymers in high yield with 5-100 repeat units and narrow molecular weight distributions. Monomers with n>l displayed monotropic or enantiotropic nematic mesophases. All polymers displayed enantiotropic nematic mesophases regardless of the spacer, molecular weight or length or the n-alkoxy substituent. Constitutional isomers of poly(5-carbo(2', 5'-bis-4( methoxybenzoyloxy)benzyloxy)bicyclo(2.2.1)hep t-2-ene)s containing laterally attached mixed phenylester/benzylester units are amorphous. Side chain liquid crystal polymers (SCLCPs), living ring opening metathesis polymerization.

Journal ArticleDOI
TL;DR: In this paper, a poly( o -anisidine) was synthesized using chemical and electrochemical methods and it has been characterized by infrared spectroscopy and X-ray diffraction, showing that steric effects of the o -methoxy substituent do not hinder polymer crystallization.

Patent
27 Mar 1992
TL;DR: In this article, a method of producing 4-ADPA is described, where aniline or substituted anilines derivatives and nitrobenzene are reacted under suitable conditions to produce 4-nitrodiphenylamine and substituted derivatives thereof.
Abstract: A method of producing 4-ADPA is disclosed wherein aniline or substituted aniline derivatives and nitrobenzene are reacted under suitable conditions to produce 4-nitrodiphenylamine or substituted derivatives thereof and/or 4-nitrosodiphenylamine or substituted derivatives thereof and/or their salts, either or both of which are subsequently reduced to produce 4-ADPA or substituted derivatives thereof. The 4-ADPA or substituted derivatives thereof can be reductively alkylated to produce p-phenylenediamine products or substituted derivatives thereof which are useful as antiozonants. A second embodiment of the invention is the tetrasubstituted ammonium salts or alkyl substituted diammonium salts of 4-nitrodiphenylamine, 4-nitrosodiphenylamine and the substituted derivatives thereof wherein each substituent of the tetrasubstituted ammonium ion is independently selected from the group consisting of alkyl, aryl and arylalkyl groups and each alkyl substituent of the alkyl substituted diammonium salt is independently selected.

Journal ArticleDOI
TL;DR: These compounds provide muscarinic ligands with high potency and a range of efficacies suitable for testing as candidate drugs in the treatment of Alzheimer's disease.
Abstract: The effect of variation of the 1-azabicyclic substituent on the novel 1,2,3-triazol-4-yl-, 1,2,4-triazol-1-yl, tetrazol-5-yl-, and tetrazol-2-yl-based muscarinic receptor ligands has been studied, and the exo-azabicyclic[2.2.1]hept-3-yl substituent was found to give the most potent and efficacious compounds. In addition, variation of the second substituent on 1,2,4-triazol-1-yl- and tetrazol-2-yl-based muscarinic receptor ligands has yielded a series of novel compounds with high potencies and efficacies, ranging from full agonists to antagonists. Small lipophilic electron withdrawing substituents give potent but low efficacy compounds, while small polar electron donating substituents give potent and efficacious compounds. The activity of these compounds is described in terms of a model of the receptor involving lipophilic and hydrogen bonding interactions. These compounds provide muscarinic ligands with high potency and a range of efficacies suitable for testing as candidate drugs in the treatment of Alzheimer's disease.


Patent
11 Feb 1992
TL;DR: In this article, the authors defined the formula (STR1) where n is 0-5, lower branched chain alkyl having 3 to 6 carbons, cyclo-alkyl having 3-to-6 carbons and 1 or 2 double bonds, alkynyl having 2-6-carbons and 2-or 2 triple bonds, and Z-Y substituent is in a 1,2 or 1,3 position on the phenyl ring relative to the ethene moiety.
Abstract: Compounds of the formula ##STR1## wherein R1, R2, R3 and R4 independently are hydrogen, lower alkyl of 1 to 6 carbons, halogen or lower alkoxy of 1 to 6 carbons; R5 and R5 ' independently are hydrogen or lower alkyl of 1 to 6 carbons; Y is oxygen or sulfur; Z is n-alkyl having 2 to 10 carbons, cyclo or branch-chained alkyl of 3 to 10 carbons, and straight chain alkenyl having 2 to 10 carbons, or cyclo or branched chained alkenyl of 3 to 10 carbons, and the Z-Y substituent is in a 1,2 (ortho) or 1,3 (meta) position on the phenyl ring relative to the ethene moiety; A is (CH2)n where n is 0-5, lower branched chain alkyl having 3 to 6 carbons, cycloalkyl having 3 to 6 carbons, alkenyl having 2 to 6 carbons and 1 or 2 double bonds, alkynyl having 2 to 6 carbons and 1 or 2 triple bonds; B is COOH or a pharmaceutically acceptable salt thereof, COOR8, CONR9 R10, --CH2 OH, CH2 OR11, CH2 OCOR11, CHO, CH(OR12)2, CHOR13 O, --COR7, CR7 (OR12)2, or CR7 OR13 O, where R7 is an alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons, R8 is an alkyl group of 1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or R8 is phenyl or lower alkylphenyl, R9 and R10 independently are hydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or phenyl or lower alkylphenyl, R11 is alkyl of 1 to 10 carbons, phenyl or lower alkylphenyl, R12 is lower alkyl, and R13 is divalent alkyl radical of 2-5 carbons, have retinoid like biological activity.

Journal ArticleDOI
TL;DR: In this article, the effect of ligand and substituent modification on high-valent transition-metal alkylidene complexes is discussed and discussed in the context of high-level alkylation.
Abstract: Article on high-valent transition-metal alkylidene complexes and the effect of ligand and substituent modification.

Patent
11 Dec 1992
TL;DR: In this paper, an aqueous ink composition is provided having up to 50 wt. % of a colorant of the formula: A, Y, X, C 2-30, substituted or unsubstituted alkylene, alkenylene or phenylenealkylene.
Abstract: An aqueous ink composition is provided having up to 50 wt. % of a colorant of the formula: A--{Y--X--C(O)--R.sub.1 --C(O)O.sup.- }.sub.p where A is an organic chromophore; Y is a polyoxyalkylene substituent; X is a radical of a reactive hydroxy, amino or thio group; and R 1 is C 2-30 , substituted or unsubstituted alkylene, alkenylene, or phenylenealkylene. A counter ion selected from alkaline metal ions, alkaline earth metal ions, ammonium ions, amine salts, and zinc ammonium complexes is present in approximately stoichiometric proportion or greater relative to the colorant in the ink composition.

Journal ArticleDOI
TL;DR: It is shown that, for compounds bearing such a substituent, only a particular combination of properties provides high activity, both in vitro and as inhibitors of gastric acid secretion in vivo.
Abstract: Previously, gastric (H+/K+)-ATPase inhibitors such as 2 have been prepared as analogues of 1a on the presumption that the 3-carbethoxy substituent plays a key role in establishing the orientation of the 4-arylamino group. In this paper we explore further the contribution made to activity by the quinoline 3-substituent. We show that, for compounds bearing such a substituent, only a particular combination of properties provides high activity, both in vitro and as inhibitors of gastric acid secretion in vivo. The ability of the substituent to affect activity by restricting rotation about the Cquin-N bond through a combination of both a pi-electron withdrawal and hydrogen bonding is supported by the current study. However, high activity is only achieved if the effect of this group on the quinoline pK(a) is kept to a minimum. 3-Acyl substituents provide an optimum combination of electronic properties. From this series, compound 17c (SK&F 96067) was shown to be a potent inhibitor of histamine-stimulated gastric acid secretion after oral dosing in the Heidenhain pouch dog and was selected for further development and evaluation in man.

Journal ArticleDOI
TL;DR: Iron(II) complexes of picket-fence-type porphyrins having one of the four pivalamide pickets replaced by a substituent capable of H-bonding have been synthetized as models for oxyhemoglobin.
Abstract: Iron(II) complexes of picket-fence-type porphyrins having one of the four pivalamide pickets replaced by a substituent capable of H-bonding have been synthetized as models for oxyhemoglobin. This synthesized as models for oxyhemoglobin. This synthetic approach is analogous to site-directed mutagenesis of the distal residues in oxygen-binding hemoproteins. Rate and equilibrium data for dioxygen binding have been determined to evaluate the effect of the H-bonding substituent and to make comparisons with more passive substituents

Patent
27 Oct 1992
TL;DR: In this paper, the pH controlled selectivity of the sulfomethylation reaction is used to prepare a series of di-, tri-, tetra-and hexaazacyclomacrocycles with specified patterns of pendent side-chain chelating groups.
Abstract: The pH controlled selectivity of the sulfomethylation reaction is used to prepare a series of di-, tri-, tetra- and hexaazacyclomacrocycles with specified patterns of pendent side-chain chelating groups. The prepared mono and diacetic acid derivatives, together with monomethylenephosphonate and monomethylenephosphinate derivatives of tetraazacyclododecane, and triazcyclododecane and [9]aneN3, make these types of ligands easily available by a synthetic pathway that avoids the use of protective groups. The invention thus comprises a variety of compounds, methods and uses characterized by relatively high synthetic yields of polyazamacrocyclic ligands exhibiting a wide and predictable choice of metal ion binding constants water and lipid solubilities by reason of their substituent pendent groups.

Journal ArticleDOI
TL;DR: This work has conducted stopped-flow kinetics association and dissociation experiments on the interaction of these anthraquinones with calf thymus DNA and with DNA polymers with alternating AT and GC base pairs to experimentally determine the binding mode and how the threading mode affects intercalation rates relative to similarly substituted classical intercalators.
Abstract: Molecular modeling studies [Islam, S.A., Neidle, S., Gandecha, B.M., Partridge, M., Patterson, L.H., & Brown, J.R. (1985) J. Med. Chem. 28, 857-864] have suggested that anthracene-9,10-dione (anthraquinone) derivatives substituted at the 1,4 and 1,8 positions with-NH(CH2)2NH(CH2CH3)2+ side chains intercalate with DNA with both substituents in the same groove (classical intercalation) while a similarly substituted 1,5 derivative intercalates in a threading mode with one side chain in each groove. Modeling studies also suggested that anthracene-9,10-dione (anthraquinone) derivatives substituted at the 2,6 positions with -NHCO(CH2)R (where R is a cationic group) should bind to DNA by the threading mode, and several such derivatives have been synthesized [Agbandjie, M., Jenkins, T.C., McKenna, R., Reszka, A., & Neidle, S. (1992) J. Med. Chem. 35, 1418-1429]. We have conducted stopped-flow kinetics association and dissociation experiments on the interaction of these anthraquinones with calf thymus DNA and with DNA polymers with alternating AT and GC base pairs to experimentally determine the binding mode and how the threading mode affects intercalation rates relative to similarly substituted classical intercalators. The binding modes, determined by analysis of relative rates, energies of activation, and effects of salt concentration on association and dissociation rate constants, agree completely with the modes predicted by molecular modeling methods. Association and dissociation rate constants for the threading mode are approximately a factor of 10 lower than constants for the classical intercalation mode, and the two modes, thus, have similar binding constants. Variations in rate constants for changes in cationic substituents at the 2 and 6 positions of the anthraquinone ring were surprisingly small.(ABSTRACT TRUNCATED AT 250 WORDS)

Journal ArticleDOI
TL;DR: The crystal and molecular structure of nitrobenzene was determined at 103 K by X-ray diffraction, yieldingR=0.034 and a highly precise geometry of the molecule (esds of bond lengths ≤ 0.001 A and bond angles ≤0.1°).
Abstract: The crystal and molecular structure of nitrobenzene was determined at 103 K by X-ray diffraction, yieldingR=0.034 and a highly precise geometry of the molecule (esds of bond lengths ≤0.001 A and bond angles ≤0.1°). The bond angles in the ring agree very well with additive scheme based on angular substituent parameters. X-X electron density maps support the view that the C-N bond does not exhibitπ-character, and, hence, the nitro group interacts with the ring mostly by inductive effects.

Journal ArticleDOI
TL;DR: In this article, the cation complexing abilities of a series of p-tert-butylcalix[4]arenes bearing ligating ester groups in the cone conformation have been assessed by stability constant measurements in methanol and extraction studies from water into dichloromethane.
Abstract: The cation complexing abilities of a series of p-tert-butylcalix[4]arenes bearing ligating ester groups in the cone conformation have been assessed by stability constant measurements in methanol and extraction studies from water into dichloromethane. The cations studied were Na+ and K+ and variations in the ester function (CO2R) included R = methyl, ethyl, n-butyl, tert-butyl, benzyl, phenyl, phenacyl, methoxyethyl, trifluoroethyl, methylthioethyl and prop-2-ynyl. The effect of replacing one or two ester functions in the tetraethyl ester by methyl ester, carboxylic acid, ketone and amide functions was also studied. Selectivities for Na+ relative to K+ in stability constants range from 2 to 2500, the phenacyl derivative having the highest selectivity. X-Ray diffraction analysis was used to probe the conformation of the trifluoroethyl ester 11. Crystals of 11 are monoclinic, space group P21/n, in a cell of dimensions a= 13.987(2), b= 16.194(3), c= 27.630(5)A; β= 98.70(1)°; R= 0.077 for 3172 observed data. The compound possesses a distorted cone conformation.

Journal ArticleDOI
TL;DR: In this paper, the boron complex of phthalonitrile with the iminoisoindoline derivatives of macrocyclic compounds was used to synthesize symmetric phthalocanines.
Abstract: Unsymmetrical phthalocanines (5–7) with a single macrocyclic substituent are synthesized by the reaction of the boron complex of phthalonitrile (1) with the iminoisoindoline derivatives 2–4 of macrocyclic compounds, i.e. 15-crown-5, monoaza-15-crown-5, and tetraazacyclotetradecane. The monomacrocycle-substituted phthalocyanines are less soluble than the tetra-substituted one.

Patent
03 Apr 1992
TL;DR: In this paper, a method of preparing.alpha.,.beta.-unsaturated ketolactones which are useful in the production of prostaglandins having one or more halogen substituent(s) at position 16 or 17 in high yield was presented.
Abstract: The present invention provides a method of preparing .alpha.,.beta.-unsaturated ketolactones which are useful in the production of prostaglandins having one or more halogen substituent(s) at position 16 or 17 in high yield, in which, a dimethyl (2-oxoalkyl) phosphonate having one or more halogen substituents (as a starting material) is reacted with a bicyclolactone aldehyde in the presence of an alkali metal hydride and a zinc compound.