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A stereodynamic chiroptical sensor based on three-component assembly of 3-(di-2-picolylaminoacetamido)-2-formyl-naphthalene (1), ZnII and amino acids was developed. The imine formed between 1 and an amino acid has six coordination sites to bind tightly ZnII ion. The crystal structure of the ZnII complex, 1-Zn-D-Phe, revealed that the naphthyl ring is tilted to one pyridine ring to generate axial chirality. The dihedral conformations observed in 1-Zn-D-Phe were herein arbitrarily designated as α1 and α2. DFT calculation suggests that the D-Phe binding prefer the α1-conformer: the energy of D-Phe-α1 is more stable than L-Phe-α1 by 5.5 kcal/mol. This preference to one diastereomer generates amplification of CD signal with Cotton effect, which can be applied to the determination of ee values of the amino acid.

New rhodamine derivatives bearing binaphthyl group were synthesized as selective fluorescent and colorimetric sensors for Cu2+. Highly selective “off–on” type fluorescent changes were observed upon the addition of Cu2+. Selective fluorescent enhancement of two rhodamine derivatives was attributed to ring opening from the spirolactam (nonfluorescent) to ring-opened amide (fluorescent). A chemo-sensing based on rhodamine derivative was further applied to the microfluidic system.

Novel binol receptor with pyrrole-2-carboxamide moiety and its analogues have been designed, synthesized, and used to enantioselectively recognize 1,2-aminoalcohols via multiple hydrogen bonding. The pyrrole-based binol receptor showed the highest enantioselectivity among the four receptors as determined by the 1 H NMR. The DFT calculation strongly supports complementary hydrogen bonding between alcoholic –OH and pyrrolyl groups.

The uryl-based binol aldehyde, (S)-2-hydroxy-2′-(3-phenyluryl-benzyl)-1,1′-binaphthyl-3-carboxaldehyde (1), binds 1,2-amino alcohols and amino acids stereoselectively by reversible formation of imine bond. Hydrogen bond (between uryl group and alcohol –OH moiety) plays an important role in the stereoselectivity of amino alcohols. Hence, any substituents on phenyl group in 1 are expected to affect H-bond ability of uryl group. To study the effects of ring substituents on the stereoselective recognition of amino alcohols, (substituted phenyl)uryl-based chiral binol receptors have been prepared. The receptors with electron-donating X substituents have been synthesized from (S)-2-methoxymethoxy-2′-hydroxy-1,1′-binaphthyl-3-carboxaldehyde and X-phenyluryl-benzyl bromide. The receptors with electron-withdrawing Y substituents, however, required a different synthetic strategy including transformation of an aldehyde to alcohol. The incorporation of the electron withdrawing groups slightly accelerated the stereoselective recognition property of the receptor. Though the acceleration is not so remarkable, this work demonstrates the versatile derivatization of 1 in achieving higher stereoselective recognition of 1,2-amino alcohols and stereoconversion of l -amino acids to d -amino acids.

A novel auxillary chiral ketone has been designed, synthesized, and used to enantioselectively recognize 1,2-amino alcohols. This work proves that the keto group can serve as a chiral recognition center by imine formation supported by resonance assisted hydrogen bonding (RAHB).

Dinuclear [Cu(aepi)(N3)2]2 (1) [aepi = 1-(2-aminoethyl)piperidine] and 1D chain [Cu(aepy)(N3)2]n (2) [aepy = 1-(2-aminoethyl)pyrrolidine] have been prepared and characterized by means of X-ray analysis and magnetic measurements. For 1, the Cu(II) centers are doubly bridged by end-on (EO) azido units in a basal–apical fashion. The molecular structure of 2 features magnetic centers that are linked by μ-1,1,3 azido groups, forming a 1D chain with alternating EO and end-to-end (EE) azido bridging patterns. The magnetic data for the dinuclear complex 1 were fitted with the Bleaney–Bowers equation derived from the Hamiltonian H = −JS1 · S2, affording parameters of g = 2.093(1), J = −3.06(1) cm−1 and zJ′ = −1.32(3) cm−1. This indicates that the EO azido group mediates an antiferromagnetic interaction. Complex 2 has two possible magnetic pathways: one is through the EO azido bridge (Jeo) and the other via the EE bridge (Jee). The alternating chain model with ferromagnetic and antiferromagnetic interactions based on the exchange Hamiltonian H = −∑i[J1S2i · S2i + 1 + J2S2i · S2i − 1] was employed, leading to g = 2.076(2), J1 = −3.22(5) cm−1, J2 = 17.0(5) cm−1 and zJ′ = −1.34(6) cm−1. By taking into account structural parameters of 1 and 2, it is rationally suggested that J1 and J2 are ascribed to Jeo andJee, respectively. These assignments are also ascertained by MO calculations using a spin dimer model.

Mono(trifluoroacetato)platinum(IV) complexes of the formula [PtIV(dach)L3(TFAc)] (dach = trans-(±)-1,2-diaminocyclohexane, TFAc = trifluoroacetate, L = acetate or propionate) could be prepared from the reaction of [PtIV(dach)L3(OH)] with trifluoroacetic anhydride in the presence of a base and the crystal structure of compound 4 was determined by X-ray crystallography. In vitro antitumor activity of complex 4 (ED50 = 3.1 μM) was found to be much higher than carboplatin (ED50 = 10.2 μM).

The reaction of [Pt(IV)(dach)(OH) 4 ] (dach= trans -(±)-1,2-diaminocyclohexane) with an excess of carboxylic acid at room temperature afforded tricarboxylatoplatinum(IV) complexes, [Pt(dach)(L) 3 (OH)] (L=acetato, propionato, valerato) in contrast to the carboxylation reaction with excess carboxylic anhydrides, which gave only tetracarboxylatoplatinum(IV) complexes as a major product. The protonation on hydroxo ligand of the platinum(IV) complex to form aqua ligand seems to be followed by nucleophilic substitution by carboxylate or chloride anion. Such nucleophilic substitution afforded only partially substituted tricarboxylatoplatinum(IV) complexes in carboxylic acid solvent whereas the reaction in 0.1 M HCl solution gave tetrachloroplatinum(IV) complex. This difference is explainable by different p K a values of the four aqua ligands, among which the last aqua ligand may have sufficiently low p K a value allowing the protonation only in strong acidic media like hydrochloric acid.

Novel trinuclear disilver(I)–copper(II) complexes, [Ag(PPh3)2]2[Cu(mtm)2] (1) and [Ag2(dppm)2][Cu(mtm)2] (2) (mtm=[bis(methylthio)methylene]malonate, dppm=bis(diphenylphosphino)methane) have been prepared and characterized by a single-crystal X-ray structure analysis. In the complex 1, a silver atom is coordinated to each of the two carboxylate oxygens with different bond distances of 2.325(5) A (AgO(1)) and 2.653(6) A (AgO(2)). In the case of the complex 2, two silver atoms are bridged by two dppm ligands separated by 3.0130(9) A and Ag(1) has bonded to O(5) (2.442(5) A). Interestingly, Ag(2) has bonded to O(4) (2.325(5) A) which is not a coordinated carboxylate oxygen bonded to copper(II) atom. Interaction between silver(I)–thioether group was not observed in 1 and 2.

A new series of quinolone-platinum(II) conjugates, [Pt(Q'-NH2)(dmso)X2] and cis-[Pt(Q"-en)X2], where Q' and Q" are quinolones (flumequine, nalidixic acid or oxolinic acid) linked to monodentate and bidentate amine ligands, respectively, and X2 is Cl2 or 1,1-cyclobutanedicarboxylate, have been synthesized with the aim of examining the synergetic antitumor activity of quinolone intercalation and platinum(II) chelation. The complexes were characterized by elemental analyses and IR and multinuclear (1H and 195Pt) NMR spectroscopies, and then subjected to in vitro and in vivo bioassays using the leukemia L1210 cell line.

Pale blue crystals were obtained from an aqueous solution containing equimolar amounts of (dmpda)Pt(N-nic) 2 (dmpda=2,2-dimethyl-1,3-propanediamine, nic=nicotinate) and copper(II) nitrate and subjected to X-ray crystallography, which revealed that the crystals are a composite material of the formula [(dmpda)Pt(N-nic) 2 ] 2 ·Cu(OH 2 ) 5 ·2NO 3 ·4.5H 2 O. Copper(II) nitrate was found to be intercalated between the platinum complex layers which were constructed by non-covalent bonding interactions such as hydrogen bonding, π–π* stacking and electrostatic interactions of the platinum(II) complex. A linear array of the intercalated cationic Cu(OH 2 ) 5 complex was observed. The value of the effective magnetic moment of the composite material is subnormal ( μ eff =1.57 BM) at room temperature.

A novel imidazolium-based binol receptor 4 has been synthesized and used as a chirality conversion reagent for general amino acids with higher d -form selectivity compared to other guanidinium-based receptors. Favorable solubility in chloroform enabled 4 as an effective chiral extractant for the resolution of racemic amino acids.

New zwitterioni (diamine)platinum(II) complexes A2Pt(ita) (A2 = 2,2-dimethyl-1,3-propanediamine (dmpa), tetrahydro-4H-pyran-4,4-diylbis(methylamine) (thpdma), trans-(±)-1,2-diaminocyclohexane (dach), ethylenediamine (en); ita = itaconate) have been synthesized and characterized by means of NMR spectroscopy and X-ray analysis. The platinum atom adopts a square-planar arrangement, in which the itaconate ligand is coordinated to the platinum atom through one carboxylate and the ethylate groups. The ethylene group occupies the fourth coordination site of the square plane, which intersects the midpoint of the CC bond axis, but the bond axis is not perpendicular to the square plane because of i ts chelated ri ng strain. Such a chelation mode is retained without linkage isomerism in aqueous solution up to 70°C.

A 1H NMR study has been carried out on (diamine)platinum(II) complexes of 1,3-dithian-2-ylidenemalonate (DTAYM) and 1,3-dithiepane-2-ylidenemalonate (DTEYM) ligands as anionic leaving group in aqueous solution. Only the O,S-chelated isomer was observed in solution for all the DTAYM complexes regardless of the kind of carrier ligand amine as was in the solid state. However, both O,S- and S,S′-chelated isomers were observed in solution for DTEYM complexes, which show linkage isomerism from the O,S-chelate to the thermodynamically more stable S,S′-chelate. The rate of linkage isomerism of the DTEYM complexes was found to be dependent on their amine co-ligands. Molecular dynamics of the DTAYM complexes was also discussed based on their temperature-dependent NMR spectra. The crystal structure of the S,S′-isomer of (NH3)2Pt(DTEYM) · H2O was determined whereas that of the O,S-isomer could not be obtained due to its poor crystallinity.

New (diamine)platinum(II) complexes of bis(alkylthio)methylenepropanedioate ligandss, A 2 Pt(RS) 2 CC(COO − ) 2 (ANH 3 or A 2  trans -(±)-1,2-diaminocyclohexane (DACH); RCH 3 or C 2 H 5 ), have been prepared and structurally characterized both in the solid state and in solution. The crystal structures of a bis(ethylthio)methylenepropanedioate (BETMP) complex, (DACH)Pt(BETMP) · 4H 2 O ( monoclinic , P2 1 , a = 11.022(2), b = 17.604(4), c = 11.426(5) A , β = 93.42(3)°, V = 2213(1) A 3 , Z = 4, R = 0.065 ). and a bis(methylthio)methylenepropanedioate (BMTMP) complex, (DACH)Pt(BMTMP) · 3H 2 O triclinic , P1, a = 9.082(3), b = 9.797(3), c = 11.493(4) A , α = 72.42(3), β = 74.28(3), γ = 84.93(3)°, V = 938.4(5) A 3 , Z = 2, R = 0.031) , exhibit that among the possible chelating modes (O,O′-, O,S− and S,S′-), the present anionic ligands coordinate to the platinum(II) atom only in S,S′-chelating fashion. The bond distances of P t -S are in the range 2.273(2)–2.276(5) A. For the title complexes, the diethyl groups of the BETMP ligand occupy anti positions to each other whereas the dimethyl groups fo the BMTMP ligand occupy syn positions in the solid state. However, NMR studies disclose that the BMTMP complexes exist as an isomeric mixture of syn and anti forms (1:2) in contrast to the retention of the anti isomeric form of the BETMP complexes in solution.

Chiral ethylenediamine ligands with free tertiary amine groups and their platinum complexes are synthesized. The platinum complexes have both chirality and additional DNA interacting groups. The hydrogen bonding interactions between chlorides and two tertiary amine groups in the crystal structure lead to the dimerization of two platinum complexes having pocket-like cavity with chiral shapes.

New platinum(II) complexes A 2 Pt(OOC) 2 CCR 2 ( 1 , A 2 = 3-aminohexahydroazepine, R 2 = −(CH 2 5 − ; 2 , A 2 = 3-aminohexahydroazepine, R = CH 3 ; 3 , A 2 = 3-aminohexahydroazepine, R 2 = −SCH 2 CH 2 S-; 4 , A = cyclopropylamine, R 2 = −SCH 2 CH 2 S-) have been prepared and characterized. The molecular structures of the representative complexes 1 · 2H 2 O and 4 · C 3 H 7 NO were determined by X-ray analysis. The platinum atoms for 1 · 2H 2 O and 4 · C 3 H 7 NO achieve a typical square planar arrangement with each nitron atom in cis position. For 1 · 2H 2 O an unusually short CC bond [1.298(18) A] has been observed in contrast to the corresponding bond [1.374(9)A] in 4 · C 3 H 7 NO. The spectroscopic and physicochemical data disclose that these platinum complexes are stable and their molecular structures are retained in aqueous solution.