Bone marrow (BM) chimeras prepared by complete recipient ablation (A-->B) exhibit donor-specific tolerance, yet survival is often limited by graft-versus-host disease (GVHD). Negative selection of potentially donor-reactive T cells, as assessed by relative T-cell receptor (TCR)-Vbeta expression, is dependent on donor BM-derived deleting ligands. Mixed chimerism and tolerance for both donor and ...

DFT-GGA method of Perdew-Burke-Ernzerhof (PBE) is used with aug-cc-PVTZ, 6-311++G**, and Def2-TZVP large basis sets to study the hydrogen bond interactions between oxygen lone pair as a donor electron with hydrogen atom connected to the aniline’s nitrogen as an electron acceptor (H2O···HNH-Ph), and nitrogen lone pair with hydrogen of water molecule (Ph-H2N···HOH...

Six-membered chelate complexes [Pd(1a-b)Cl2], (2a-b) and [Pd(1a-b)(η(3)-PhCHCHCHPh)]BF4, (3a-b) of P,N-type ligands 1a, ((2S,4S)-2-diphenyl-phosphino-4-isopropylamino-pentane) and 1b, ((2S,4S)-2-diphenyl-phosphino-4-methylamino-pentane) have been prepared. The Pd-complexes have been characterized in solution by 1D and 2D NMR spectroscopy. The observed structures were confirmed by DFT calculatio...

covalent grafting of mcm-41 with 3-chloropropyl trimethoxysilane and subsequent reaction respectively with acacdien and complexation with moo2(acac)2 afforded moo2acacdien@mcm-41. x-ray diffraction and nitrogen sorption analyses revealed the preservation of the textural properties of the support as well as accessibility of the channel system despite sequential reduction in surface area, pore vo...

The molecular chemistry of the f-elements, i.e. the lanthanides and actinides, is traditionally dominated by the use of carbon, nitrogen, oxygen or halide ligands. However, the use of metal-based fragments as ligands is underdeveloped, which contrasts to the field of d-block metal–metal complexes that have developed extensively over the last 50 years. Consequently, the use of metal-based fragme...

Two bidentate Schiff base ligands having nitrogen sulphur donor sequence were derived from the condensation of S-benzyldithiocarbazate (SBDTC) with 2-chloroacetophenone and 4-chloroacetophenone to give S-benzyl- β -N-(2-chlorophenyl)methylenedithiocarbazate (NS2) and S-benzyl- β -N-(4-chlorophenyl)methylenedithiocarbazate (NS4) isomers. Each of the ligands was then chelated with Cd(2+), Zn(2+),...

Two bidentate NS ligands were synthesized by the condensation reaction of S-2-methylbenzyldithiocarbazate (S2MBDTC) with 2-methoxybenzaldehyde (2MB) and 3-methoxybenzaldehyde (3MB). The ligands were reacted separately with acetates of Cu(II), Ni(II) and Zn(II) yielding 1:2 (metal:ligand) complexes. The metal complexes formed were expected to have a general formula of [M(NS)2] where M = Cu2+, Ni...

Z. Naturforsch. 56 b, 735-746 (2001); eingegangen am 16. Februar 2001 2,4-Dicyano Glutaconic Acid Diethyl Ester Anion, Cyano Bridges, Helix The anion of 2,4-dicyano glutaconic acid diethyl ester, [NCC(COOEt)CHC(COOEt)CN]_ ( I ), as an a,u;-dinitrile with a three atom spacer is a highly variable ligand capable of binding in a monodentate 77'-fashion, in a bidentate chelate fashion, and as a p 2-...

Using a metal-ligand coordination bonding approach, the self-assembly of four new metallamacrocycles from Pd(ii)-based 90 degrees acceptors and a diimidazole donor ligand 1,3-bis(imidazole-1-ylmethyl)-2,4,6-trimethylbenzene (L) has been achieved. The assemblies are characterized fully by NMR and electrospray ionization-mass spectroscopic (ESI-MS) analysis and in two cases the X-ray single-cryst...