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A bulky platinum triamine complex, [Pt(Me 5 dien)(NO 3 )]NO 3 (Me 5 dien = N,N,N′,N′,N″ -pentamethyldiethylenetriamine) has been prepared and reacted in D 2 O with N-acetylmethionine (NAcMet) and guanosine 5′-monophosphate (5′-GMP); the reactions have been studied using 1 H NMR spectroscopy. Reaction with 5′-GMP leads to two rotamers of [Pt(Me 5 dien)(5′-GMP-N7)] + . Reaction with N-AcMet leads to formation of [Pt(Me 5 dien)(N-AcMet-S)] + . When a sample with equimolar mixtures of [Pt(Me 5 dien)(D 2 O)] 2+ , 5′-GMP, and N-AcMet was prepared, [Pt(Me 5 dien)(5′-GMP-N7)] + was the dominant product observed throughout the reaction. This selectivity is the opposite of that observed for a similar reaction of [Pt(dien)(D 2 O)] 2+ with 5′-GMP and N-AcMet. To our knowledge, this is the first report of a platinum(II) triamine complex that reacts substantially faster with 5′-GMP than with N-AcMet; the effect is most likely due to steric clashes between the methyl groups of the Me 5 dien ligand and the N-AcMet. Keywordsnuclear magnetic resonance; ligand binding; anticancer drug; platinum Cisplatin and its analogs are known to form 1,2-intrastrand cross-links with guanine that lead to DNA distortion and are considered responsible for cytotoxicity. However, reaction with proteins, especially at methionine residues, occurs readily [1,2]. Protein adducts could be responsible for toxicity or resistance [3]. Previous small molecule studies have shown that [Pt (dien)Cl]Cl (dien = diethylenetriamine) reacts faster both with methionine (Met) [4] and with S-methylglutathione [5] than with guanosine 5′-monophosphate (5′-GMP).We previously found that bulk on a platinum diamine compound can affect the N-AcMet adducts that can form. [Pt(N,N,N′,N′ -tetramethylethylenediamine)(D 2 O) 2 ] 2+ reacts with NAcMet in only a 1:1 ratio even when excess N-AcMet is present, forming a chelate via the sulfur and carboxylate oxygen atoms [6]. Molecular mechanics calculations suggested severe steric clashes in a 2:1 N-AcMet:Pt complex. Later work with [Pt(N,N-diethylethylenediamine) (D 2 O) 2 ] 2+ indicated only one geometric isomer of the observed sulfur-oxygen chelate, namely the one with the sulfur atom trans to the diethyl nitrogen [7]. Thus, coordination of a methionine sulfur atom cis to a bulky amine nitrogen is apparently slowed considerably. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Replacement of the amine hydrogens of dien with methyl groups would have several possible effects. First, a difference in observed trans effect would be possible, as Me 5 dien has an a methyl group on the N tr...

The main purpose of this quantitative study was to examine the degree to which a three‐week intervention in an urban high‐needs high school science classroom would influence students’ (n = 51) interest, utility value, content knowledge, and intentions for future study in chemistry. The intervention consisted of an authentic, inquiry‐based chemistry project where students worked cooperatively to investigate core chemistry concepts and connect them to real‐world consumer products and careers in manufacturing that required chemistry knowledge. Findings indicated that students improved their chemistry knowledge, found greater relevance for chemistry, and intend to take more chemistry in the future. Interest in chemistry did not statistically significantly increase as a result of the intervention; however, students’ interest levels remained consistently moderate from pre‐test to post. This study adds to the current body of literature in three ways. First, the intervention showcased positive outcomes with students from an urban, high‐needs high school who lacked motivation and academic proficiency in science. Second, using an authentic, inquiry‐based utility value intervention is a viable alternative to previous successful interventions that involved writing tasks. Finally, the study was the result of a high school teacher's advanced training in research where important evaluation skills were cultivated and advanced.