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G Ferguson

Publications and source records attributed to G Ferguson.

At least 19 recordsLinked to original sources
PubMed2001

A hydrogen-bonded adduct containing seven-component supramolecular aggregates.

The title compound is a salt, 3,6,9,16,19,22-hexaazatricyclo[22.2.2.2(11,14)]triaconta-1(26),11(29),12,14(30),24,27-hexaene-3,5-dinitrobenzoic acid-methanol (1/4/2), C24H42N6(4+).4C7H3N2(O6)(-).2CH4O, in which the cation lies across a centre of inversion and one of the two independent anions is positionally disordered over two sets of atom sites having equal occupancy. The components are linked by four types of N-H...O hydrogen bond [N...O 2.674 (2)-2.815 (2) A; N-H.O 149-163 degrees] and one type of O-H...O hydrogen bond in which the acceptor is disordered over two closely adjacent sites [O...O 2.67 (4) and 2.75 (4) A; O-H...O 172 and 173 degrees], forming centrosymmetric seven-component aggregates.

Journal Article↗
PubMed2001

A three-dimensional hydrogen-bonded framework in 4,4'-trimethylenedipiperidinium-2,5-dicarboxybenzene-1,4-dicarboxylate-water (1/1/1).

The title compound is a salt, C13H28(N2)(2+).C10H4(O8)(2-).H2O. In the anion, there are two short intramolecular hydrogen bonds [O.O 2.395 (2) and 2.383 (2) A; O.H.O 175 and 172 degrees]. Pairs of anions and pairs of water molecules are linked by further O-H.O hydrogen bonds [O.O 2.756 (2) and 2.980 (2) A; O-H.O 171 and 175 degrees] into cyclic centrosymmetric R(6)(6)(16) aggregates; these aggregates are linked via the cations into a three-dimensional framework by means of four distinct N-H...O hydrogen bonds [N...O 2.787 (2)-3.204 (2) A; N-H...O 148-173 degrees].

Journal Article↗
PubMed2001

Hydrogen-bonded sheets in the 1:1 salt of tet-b and trimesic acid.

Tet-b (racemic 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, C(16)H(36)N(4)) and trimesic acid (1,3,5-benzenetricarboxylic acid, C(9)H(6)O(6)) form a salt partially solvated by both water and methanol, i.e. 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-1,3,5-benzenetricarboxylic acid--methanol--water (1/1/0.78/1.12), C(16)H(38)N(4)(2+) x C(9)H(4)O(6)(2-) x 0.78CH(4)O x 1.12H(2)O. The anions are linked by O--H...O hydrogen bonds [O...O 2.442 (4) and 2.458 (4) A; O--H...O 170 and 171 degrees ] into zigzag chains; orientationally disordered cations are linked to the anion chains by means of N--H...O hydrogen bonds [major orientation: N...O 2.695 (3)--3.071 (4) A, N--H...O 148--179 degrees; minor orientation: N...O 2.75 (2)--3.34 (2) A, N--H...O 147--170 degrees ] and link the chains into sheets. The solvent molecules are all disordered, but appear to play no significant structural role apart from space filling.

Journal Article↗
PubMed2001

Ethane-1,2-diphosphonic acid as a building block in supramolecular chemistry; a pillared-layer framework and framework-encapsulated cations.

The 1:1 adduct of piperazine and ethane-1,2-diphosphonic acid is a salt [C(4)H(12)N(2)](2+).[C(2)H(6)O(6)P(2)](2-), in which both ions lie across centres of inversion in space group P2(1)/c. The anions are linked by a single type of O-H...O hydrogen bond [O...O, 2.562 (3) A; H...O, 1.73 A, O-H...O, 169 degrees ] into (6, 3) nets built from a single type of R(4)(4)(22) ring. The cations lie between these nets, linked to them by two types of N-H...O hydrogen bond [N...O, 2.635 (3) and 2.735 (3) A; H...O 1.72 and 1.82 A, N-H...O, 175 and 177 degrees ] such that the cations link adjacent sheets, thus forming a pillared-layer framework. The aquated adduct formed between trimethylenedipiperidine and ethane-1,2-diphosphonic acid is also a salt [C(13)H(28)N(2)](2+).[C(2)H(6)O(6)P(2)](2-).2.8[H(2)O], in which there are 12 different types of hydrogen bond, eight O-H...O and four N-H...O. The anions are linked into chains by pairs of O-H...O hydrogen bonds and these chains are linked by the water molecules into a continuous three-dimensional framework. Within the anion/water framework are large voids which contain pairs of cations, linked to the framework by N-H...O hydrogen bonds.

Journal Article↗
PubMed2001

Salts of 3,5-dinitrobenzoic acid with organic diamines: hydrogen-bonded supramolecular structures in one, two and three dimensions.

The trigonally trisubstituted carboxylic acid 3,5-dinitrobenzoic acid, (O(2)N)(2)C(6)H(3)COOH, forms 2:1 salts with a range of organic diamines L, with the general composition [LH(2)](2+) x [[(O(2)N)(2)C(6)H(3)COO](-)](2). When L is a bis-tertiary amine the hard N-H...O hydrogen bonds generate finite three-component aggregates, anion...cation...anion, and these aggregates are further linked by soft C-H...O hydrogen bonds to form one-dimensional molecular ladders when L is N,N,N',N"-tetramethyl-1,2-diaminoethane and chains of rings when L is 4,4'-dipyridylethane or 4,4'-dipyridylethene; two-dimensional sheets are formed when L is 1,4-diazabicyclo[2.2.2]octane and a three-dimensional framework is formed when L is N,N'-dimethylpiperazine. When L is the bis-secondary amine piperazine, the hard N-H...O and soft C-H...O hydrogen bonds each generate continuous motifs in the form of distinct chains of rings, the combination of which generates sheets, while when L is the bis-primary amine 1,2-diaminoethane the hard N-H...O hydrogen bonds alone generate a three-dimensional framework.

Journal Article↗
PubMed2000

N-(6-Amino-3,4-dihydro-3-methyl-5-nitroso-4-oxopyrimidin-2-yl) derivatives of glycine, valine, serine, threonine and methionine: interplay of molecular, molecular-electronic and supramolecular structures.

In each of N-(6-amino-3, 4-dihydro-3-methyl-5-nitroso-4-oxopyrimidin-2-yl)valine, C(10)H(15)N(5)O(4) (3) (orthorhombic, P2(1)2(1)2(1)), N-(6-amino-3, 4-dihydro-3-methyl-5-nitroso-4-oxopyrimidin-2-yl)serine monohydrate, C(8)H(11)N(5)O(5).H(2)O (4) (orthorhombic, P2(1)2(1)2(1)), and N-(6-amino-3, 4-dihydro-3-methyl-5-nitroso-4-oxopyrimidin-2-yl)threonine, C(9)H(13)N(5)O(5)(5) (monoclinic, P2(1)), the C-nitroso fragments exhibit almost equal C-N and N-O bond lengths: the C-N range is 1. 315 (3)-1.329 (3) A and the N-O range is 1.293 (3)-1.326 (3) A. In each compound there are also very short intermolecular O-H.O hydrogen bonds, in which carboxyl groups act as hydrogen-bond donors to the nitrosyl O atoms: the O.O distances range from 2.440 (2) to 2. 504 (4) A and the O-H.O angles lie between 161 and 163 degrees. An interpretation of the relationship between the unusual intramolecular bond lengths and the very short intermolecular hydrogen bonds has been developed based on database analysis and computational modelling. In each of (3)-(5) there is an extensive network of intermolecular hydrogen bonds, generating three-dimensional frameworks in (3) and (5), and two-dimensional sheets in (4).

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PubMed2000

Ets domain transcription factor PE1 suppresses human interstitial collagenase promoter activity by antagonizing protein-DNA interactions at a critical AP1 element.

In MC3T3E1 calvarial osteoblasts, fibroblast growth factor receptor (FGFR) signaling elicits multiple transcriptional responses, including upregulation of the interstitial collagenase/matrix metalloproteinase 1 (MMP1) promoter. FGF responsiveness maps to a bipartite Ets/AP1 element at base pairs -123 to -61 in the human MMP1 promoter. Under basal conditions, the MMP1 promoter is repressed in part via protein-DNA interactions at the Ets cognate, and minimally two mechanisms convey MMP1 promoter upregulation by FGF2: (a) transcriptional activation via Fra1/c-Jun containing DNA-protein interactions at the AP1 cognate and (b) derepression of promoter activity regulated by the Ets cognate. To identify osteoblast Ets repressors that potentially participate in gene expression in the osteoblast, we performed reverse transcription-polymerase chain reaction (RT-PCR) analysis of mRNA isolated from MC3T3E1 cells, using degenerative amplimers to the conserved Ets DNA binding domain to survey the Ets genes expressed by these cells. Six distinct Ets mRNAs were identified: Ets2, Fli1, GABPalpha, SAP1, Elk1, and PE1. Of these, only PE1 has extensive homology to the known Ras-regulated Ets transcriptional repressor, ERF. Therefore, we cloned and characterized PE1 cDNA from a mouse brain library and performed functional analysis of this particular Ets family member. A 2 kb transcript was isolated from brain that encodes a approximately 57 kDa protein; the predicted protein contains the known N-terminal Ets domain of PE1 and a novel C-terminal domain with signficant homology to murine ERF. The murine PE1 open reading frame (ORF) is much larger than the previously reported human PE1 ORF. Consistent with this, affinity-purified rabbit anti-mouse PE1 antibody specifically recognizes an approximately 66 kDa protein present only in the nuclear fraction of MC3T3E1 osteoblasts. Recombinant PE1 binds authentic AGGAWG Ets DNA cognates, and transient transfection studies demonstrate that PE1 represses MMP1 promoter activity. Surprisingly, although deletion of the MMP1 Ets cognate at nucleotides -88 to -83 abrogates FGF2 induction, it does not prevent suppression of the AP1-dependent MMP1 promoter by PE1. PE1 regulation maps to the MMP1 promoter region -75 to -61, suggesting that PE1 suppresses transcription via protein-protein interactions with AP1. Consistent with this, recombinant GST-PE1 specifically inhibits the formation of protein-DNA interactions on the MMP1 AP1 site (-72 to -66) when present in an admixture with MC3T3E1 crude nuclear extract. In toto, these data indicate that PE1 participates in the transcriptional regulation of the MMP1 promoter in osteoblasts. As observed with other transcriptional repressors of MMP1 gene expression, transcriptional suppression by PE1 occurs via inhibition of AP1-dependent promoter activity.

Amino Acid Sequence↗
PubMed2000

1,3-Calix

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Journal Article↗
PubMed2000

trans-Chloro(2-nitrobenzenethiolato-S)bis(triphenylphosphine-P)pallad ium(II) monoacetone solvate

Molecules of the title compound, [PdCl(C(6)H(4)NO(2)S)(PPh(3))(2)]. C(3)H(6)O, exhibit a slight distortion from exact planarity at the Pd atom towards tetrahedral, with P-Pd-P and Cl-Pd-S angles of 174. 98 (3) and 174.19 (3) degrees, respectively. The Pd-Cl and Pd-S bonds are, respectively, long [2.3550 (11) A] and short [2.3020 (12) A] for their types; the S-C bond is also very short [1.744 (4) A]. The solvating acetone molecule is linked to one of the phosphine ligands by means of a C-H.O hydrogen bond.

Journal Article↗
PubMed2000

Threefold interweaving of (4,4) nets built from R(10)10(58) rings inthe hydrogen-bonded adduct 1,4-diazabicyclo

The 1:1 adduct of 1,4-diazabicyclo[2.2.2]octane and 5-hydroxyisophthalic acid is a salt, [H(C(6)H(12)N(2))](+). [HOC(6)H(3)(COOH)COO](-) or C(6)H(13)N(2)(+).C(8)H(5)O(5)(-). The ions are linked by three types of hydrogen bond, i.e. N-H.O, O-H.O and O-H.N, into continuous two-dimensional (4,4) nets built from a single type of R(10)(10)(58) ring. Six independent sheets of this type make up the structure and these are interwoven in sets of three.

Journal Article↗
PubMed2000

Adducts of meso and racemic 5,5,7,12,12,14-hexamethyl-1,4,8, 11-tetraazacyclotetradecane with trigonally trisubstituted benzene carboxylic acids: supramolecular structures in one and two dimensions

The meso and racemic forms of 5,5,7,12,12,14-hexamethyl-1,4,8, 11-tetraazacyclotetradecane, C(16)H(36)N(4) (tet-a and tet-b, respectively), form adducts with trigonally trisubstituted benzene carboxylic acids; tet-a-3,5-dinitrobenzoic acid (1/2) (1), tet-a-5-hydroxyisophthalic acid-water (1/1/1) (3) and tet-b-5-hydroxyisophthalic acid-water (1/1/1) (4) are all salts, [C(16)H(38)N(4)](2+).2[C(7)H(3)N(2)O(6)](-) (1) and [C(16)H(38)N(4)](2+).[C(8)H(4)O(5)](2-).H(2)O (3) and (4). The conformations of the [(tet-a)H(2)](2+) and [(tet-b)H(2)](2+) cations are entirely different: [(tet-a)H(2)](2+) is precisely centrosymmetric in (1) and approximately so in (3), while [(tet-b)H(2)](2+) has approximate C(2) symmetry in (4). In each salt the cation forms two intramolecular N-H.N and four intermolecular N-H.O hydrogen bonds. In (1) the supramolecular structure is one-dimensional, a C(2)(2)(13)[R(2)(4)(16)] chain of rings. Compounds (3) and (4) crystallize in space groups P2(1)2(1)2(1) and P2(1)/c, respectively, but the supramolecular structures are very similar: in each, the anions and the water molecules form a C(7)[R(3)(3)(13)] chain of rings, generated in (3) by a 2(1) axis and in (4) by a glide plane. These chains are linked, in both (3) and (4), by cations to form sheets. Adjacent meso cations in (3) are related by a 2(1) axis and adjacent chiral cations in (4) are related by a glide plane.

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