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For many years, the U.S. has underutilized its human resources, as evidenced by the pervasive underrepresentation of several racial and ethnic groups within academia in general and the science, technology, engineering, and mathematics (STEM) disciplines, in particular. To address this underutilization, academic departments within U.S. universities must develop grassroots efforts that both recruit and retain students from all segments of the U.S. population. While many departments have noted this need and are earnestly trying to increase the diversity of their programs, very few have successfully achieved this laudable goal. This inquiry into the salient features of successful diversity agendas within STEM academic departments provides key insights into "how" departments can increase and sustain the doctoral degree attainment of students from underrepresented racial and ethnic minority groups.

The fac-[Re[(CO).sub.3]L] complexes with less elaborate prototypical ligands are examined in order to describe the baseline behavior and define parameters useful for assessing the effects of the pendant groups. The interaction of the complex with solvent as well as with the chloride anion is examined.

The investigation of fac-[[Re[(CO).sub.3][([H.sub.2]O).sub.3]].sup.} cation shows that the putative DNA-binding species accounting for the biological activity of related Re(I) complexes, binds reversibly to N7 and 6-oxopurine nucleotide monophosphates (NMPs), in contrast to Pt(II) anticancer drugs.

The synthesis and characterization of Re complexes, which are used for interpreting the nature of tracer [super 99m]Tc radiopharmaceuticals, are described. The chemistry of Re analogues with [LAN.sup.2-]are used for designing new small agents and tagging large agents because two uncoordinated carboxyl groups are available for conjugation with biological molecules such as proteins.

Femtosecond transient IR and visible absorption spectroscopies are employed to investigate the excited-state photophysics of vitamin B12 (cyanocobalamin, CNCbl) and the related cob(III)alamins, azidocobalamin (N(sub 3)Cbl), and aquocobalamin (H(sub 2)OCbl). The results suggest that the transient intermediate state is attributed to a corrin ring pi to Co 3d(sub Z)2 ligand to metal charge transfer (LMCT) state.

The presence of asymmetric carbon centers in the chelate rings of primary diamine ligands has very little effect on the properties of 12-mer oligonucleotide adducts bearing one Pt-G,G intrastrand cross-link. Replacing one of the NH groups on each nitrogen of diamines with an alkyl group and adding bulk to the ligand results in an unusual stability of the duplex form of DNA, due to unfavorable destabilizing interactions of the N-alkyl substituents with the flanking DNA of the single strand forms.

A study was conducted on the coordination capabilities of ligands (ENDACH2 and ENACH) with aliphatic amines as the only nitrogen donors toward the fac-{M(CO)3} core. Tridentate ligation was observed when two sp(super 3) nitrogen donors and at least one sp(super 3) carboxyl oxygen donor were available.

Research has been conducted on the N,N'-dimethyl-2,3-diaminobutane retro model adduct. The properties and conformer distribution of these adducts have been investigated and the results are reported.

Research has been conducted on the X-ray structurally characterized rhenium complexes. The preparation of these complexes from the protected amine-diamine-thiol ligands is discussed.

Research has been conducted on cisplatin which is widely used against the tumors. The results of the rapid atropisomerization of cisplatin-DNA cross-link models indicate that the first-to-second-sphere communication in aqueous solutions is not important, for the head-to-tail form especially.

Research discusses the synthesis of organocobalt derivatives of tetracationic water-soluble porphyrins via a new reductive alkylation using sodium borohydrate as the reducing agent. Further, the binding interactions of the new cations with DNA and synthetic DNA polymers along with their photochemical behavior are presented.

The existence of hyper-long axial Co(II) bonds in cobinamide B12 models is investigated using electron paramagnetic resonance spectroscopy.

Research has been conducted on the N,N'-dimethylpiperazine carrier ligand models. The use of the nuclear magnetic resonance spectroscopy is discussed.

Research has been conducted on Me (sub)3 dien and [PtX(Me (sub)3 dien)]X (X=I, NO (sub)3). The synthesis and characterization of these ligands are presented.

Research has been conducted on the factors that influence the dynamic motion of planar N-donor heterocyclic ligands. The use of X-rays and NMR in investigating mixed-ligand mu-oxorhenium dimers is discussed.

Research has been conducted on the N,N'-dimethylthiourea as a monoadduct trap. Experiments with a d(A (sub)1 T (sub)2 G (sub)3 G (sub)4 G (sub)5 T (sub)6 A (sub)7 C (sub)8 C (sub)9 C (sub)10 A (sub)11 T (sub)12) (sub)2 analogue with a hairpin form are examined.

Research has been conducted on the radiopharmaceuticals. The factors leading to one isomeric species in one ionization state at physiological pH are analyzed.

Research was conducted to examine the synthesis, structure and solution forms of anti- and syn-Reo(L-cysteine-acetyl-cysteamine) and the dimethyl derivatives anti- and syn-ReO(L-penicillamine-acetyl-cysteamine). Results indicate that the introduction of an electron-withdrawing group into the ligand may lower the NH pKa of the complex below the physiologically relevant range and yield a species with a well-defined charge.

The primary problem which conceals the role of the ammine and primary amine groups in the activity of clinically utilized Pt anticancer drugs is the dynamic nature of adducts with DNA and DNA constituents. This problem was solved through a hybrid ligand approach with the diamine pipen = 2-(aminomethyl)piperidine. Results showed that preferential interligand phosphate-NH hydrogen-bonding interactions between two cis 3'-GMPs stabilize the Delta over the Lambda head-to-tail atropisomer and elucidate on circular dichroism enhancement.

Imidazole-containing B(sub 12) model complexes that could be deprotonated at the imidazole NH to form the corresponding imidazolato complexes were investigated. To this end, organomethyl complexes of cobaloxime and imine/oxime analogues with equatorial ligands having an O-BF(sub 2)-O moiety in place of each deprotonable O-H- - -O moiety of standard models were synthesized. The desired monomeric imidazolato complexes were not formed at a characterizable level.

A study was conducted to analyze imidazole rings bound to metals by one-bond 1H-13C couplings. The Siemens CCD SMART Area Detector System was utilized to analyze the x-ray structures. Space groups were then assigned based on systematic absences. In addition, the GE GN-600 Omega spectrometer was utilized to obtain spectra. Experimental results indicated that shifts of close-in carbons are influenced by steric effects.

The influence of the N9 substituent in guanine analogues on conformer distribution in the chirality-controlling chelate (CCC) ligand derivative (CCC)PtG2 with CCC = N,N'-dimethyl-2,3-diaminobutane was investigated. Nuclear magnetic resonance and circular dichroism spectroscopic analyses were performed for this purpose. Experimental results showed that the L or R tilt of (CCC)PtG2 is determined by the CCC ligand, as is the size of the tilt of atropisomers.

The structural, molecular and spectroscopic properties of B12 cobaloxime and imine/oxime model complexes were investigated. Experimental results showed that the cobaloximes with pyridine and benzimidazole ligands exhibit an A-type conformation regardless of the strength of the trans influence of the ligand opposite to the N-donor heterocyclic ligand. Slight reduction of the van der Waals parameters for both the N donors and the C(sp(super 2)) atoms linked to the N donors improved the fit of the calculated and experimental structures of the model complexes.

The anticancer activity of cisplatin and its analogues is often linked to the unique intrastrand d(GpG) lesion with Pt cross-linked N7 of the adjacent anti G of DNA. The cross-link is thought to adopt an anti, anti head-to-head (HH) conformation. The existence of a single-stranded cis-Pt(d(GpG))-A(sub2) cross-link adduct in multiple conformations in slow exchange is demonstrated, and there is evidence for a novel cis-Pt(d(GpG))A(sub2) conformer HH2, which has two anti G's and HH bases.

A study is conducted on the response of the Co-CH3 moiety to changes in the trans ligand using methylcobaloximes containing abiological P-donor ligands. It is shown that in a series of methylcobaloximes (LCo(DH)2CH3 where DH = monoanion of dimethylglyoxime), the influence of P-donor ligands (L) on one-bond proton-carbon coupling constant values of the Co-CH3 moiety agrees with the pKa of L except when L was bulky. (Cy3P and i-Pr3P).

A study is conducted on (Me2DAP)Pt(G)2 complexes (G = N9-substituted guanine derivative; Me2DAP = 2,4-bis(methylamino)pentane with N, C, C, and N stereochemistries of S,R,S,R, S,R,R,R and R,R,R,R) using NMR and CD spectroscopy and molecular mechanics and dynamics calculations. Results show that the favored Me2DAP chelate ring conformations were chair. Two head-to-tail rotamers and one or two head-to-head rotamers were also observed.

The conformers of cis,cis,cis-RuCl2(Me2SO)2(3,5-lut)(1,2-Me2Im) (3,5-lut = 3,5-lutidine, 1,2-Me2Im = 1,2-dimethylimidazole) in fluxional equilibrium in solution were observed to be trapped and almost unaltered in the solid state. These presented a rare example in which the solid state closely reflects the solution state, both in the structure of species involved in a conformational equilibrium and in the position of that equilibrium.

Research was conducted to examine the use of high-resolution one-bond 1H-13C coupling constants (1J(sub CH)) for the identification of electronic changes within imidazole rings of samples containing 13C in natural abundance. J-coupled heteronuclear multiple quantum coherence (JHMQC), the reverse detection method used, employed a modified HMQC pulse sequence. Results indicate that the JHMQC method that was developed is very versatile and can offer information on any type of molecule showing resolved CH signals.

H NMR spectroscopy, X-ray crystallography and molecular mechanics/dynamics (MMD) calculations were used to prepare and study (PtXsub2(Mesub2DAP)) complexes. An understanding of the conformations of the coordinated ligands was gained, and the study provides a useful base for investigating the utility of a molecular mechanics/dynamics method, using a force field suited to nucleic acids.

A series of ruthenium complex - 4-pyridyl/phenyl porphyrins is designed, synthesized and spectrally characterized. Ruthenium complex - 4-pyridyl/phenyl porphyrins ratios of 1:1 and 1:2 for monomers, 2:1 for dimers and 4:1 for tetramers were used in the analysis. These newly described adducts have self-assembling properties and are seen as a new type of building blocks.

Biochemical research involving a novel class of organocobalt models [LCo(N-CH2-CHEL)]X shows steric bulk binding interaction differences between the ligands of the analogs 1,5,6-trimethylbenzimidazole and N-methylimidazole. Evidence indicates that steric interactions involving the equatorial ligand do not determine the angle of Co-N(5)-C bonds. The highly distorted N4 equatorial ligation seems to be caused by the Me3Bzm Lone pair of electrons.

The complete structural profiles of tallysomycin-Zn (ZnTLMA) and bleomycin-Zn (Zn-BLM2) were analyzed by nuclear magnetic resonance (NMR) spectroscopy to characterized their molecular dynamics. NMR analysis of ZnTLMA and ZnBLM2 indicated the presence of similar ligation sites or identical binding domains. Furthermore, formation of the TLMA-metal complex was characterized by the ligation of N donors such as beta-aminoalanine amines and pyrimidinylpropionamide pyrimidine.

The properties of organocobalt B12 model complexes derived from imine/oxine-type of cobalt complexes were analyzed by X-ray crystallography. Analysis of the Me3Bzm imine/oxine type B12 model complexes indicated the similar electron-donating ability and key bond lengths of the organocobalt complexes compared with cobaloxime complexes. The imine/oxime-type complexes also exhibited longer Co-C bonds due to the steric effects between the axial and equatorial ligands.

The structure of [AsPh4][EtSCo(DH)2(CH3)] was analyzed by X-ray crystallography to determine the characteristics of the organocobalt complex. The organocobalt complex is composed of a unidendate coordinated thiolate with a long C-S bond due to the weak trans influence of the thiolate to the Co-C bond. Furthermore, the alkanethiolate ligand is comparable to alkylphosphines in its affinity for axial coordination to B12 models.

Three types of methyl imine/oxime B12 model compounds are subjected to near-infrared Fourier transform-Raman spectroscopy to compare the influence of the trans ligand on vibrations of the Co-CH3 bonds with LCo(DH)2CH3 organocobalt models. The X-ray structures for the Co-C bond length and the Co-CH3 stretching frequency have good correlations such that the latter is used as a measure of trends in Co-C bond strength and bond length. The changes in N-donor ligand strength have a small effect on the frequency and consequently, with the Co-C bond strength in the ground state.

The behavior of Hg(II) with three DNA polymers d(ATGGGTTCCCAT), T2, d(GCGCTTTGCGC), T3, and d(GCGCTTTTGCGC), T4, is investigated using UV, CD and 1D/2D NMR spectroscopy. Variations in UV and CD spectra of the oligos following Hg(II) binding show good correlations with a number of both natural and prepared DNAs. The data are also consistent with those of NMR at less than Hg(II):strand ratios. The duplex form of the oligos is maintained by Hg(II) with self-complementary sequences flanking the (T)2 and (T)3 sequences. Hg(II) favors T-Hg-T formation over A-Hg-T in the Hg-T2 duplex.

Exchange-NOE nuclear magnetic resonance spectroscopy data is shown to be an efficient method for determining the extent of planar N-donor heterocyclic coordinated ligands (L's) rotation about the metal-N bond, the direction of L rotation and even the halves of C2-symmetrical L's that interchange during dynamic processes. It marks the first time that preferred pathways of rotation were demonstrated.

Near-infrared FT-Raman spectroscopic studies of B(sub 12) imidazole derivatives and cobalamins in biologically relevant aqueous solutions provide insight into the effects of replacing 5,6-dimethylbenzimidazole (DBMz) by imidazole in human enzymes. Methylcobinamide (MeCbi+) derivatives facilitate such studies. The replacement of DBMz by imidazole and imidazolate has small impacts on Raman bands of both the axial bond and the corrin. This substitution does not involve the methylcobalt(III) corrinoid ground state. Important properties of imidazole are discussed.

The reaction of thiol-amide-thiourea (TATU) ligand with Re(superV)O complexes yields (1-phenyl-3-(2-((2-thioacetyl)amino)ethyl)thioureato)oxorhenium(V) neutral complex, which is a new N2S2 chelate. The complex has a pseudo square pyramidal geometry with deprotonated thiol S, amide N, thiourea N, and thiocarbonyl S in the basal plane, and oxo group at the apical position. The thiourea unit of TATU ligands forms a four-membered chelate ring, which enables it to synthesize multidentate ligands. X-ray crystallography and NMR spectra are used to characterize the complex.