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Phosphine-promoted cross-coupling reactions of propargylcopper reagents and alkenyl iodides and the total synthesis of (-)-gloeosporone via nickel-catalyzed epoxide-alkyne reductive macrocyclization
(Massachusetts Institute of Technology, 2007)
I. Phosphine-Promoted Cross-Coupling Reactions of Propargylcopper Alkenyl Iodides Reagents and Alkenyl Iodides. An electron-rich phosphine additive is critical and sufficient for propargyl-selective couplings of propargylcopper ...
Biochemical characterization of the E. coli Very Short Patch Repair pathway and its coordination with methyltransferase repair of 0⁶-methylguanine
(Massachusetts Institute of Technology, 2006)
The E. coli Very Short Patch Repair (VSPR) system corrects T:G mismatches that arise through Dcm-mediated methylation and subsequent deamination of the underlined cytosine residue in the palindromic sequence 5'-CCWGG-3' ...
Phosphorescent semiconductor nanocrystals and proteins for biological oxygen sensing
(Massachusetts Institute of Technology, 2011)
Oxygen is required for cellular respiration by all complex life making it a key metabolic profiling factor in biological systems. Tumors are defined by hypoxia (low pO2), which has been shown to influence response to ...
Synthesis and determination of the absolute configuration of Armatol A through a polyepoxide cyclization cascade : revision of the proposed structures of Armatols A-F
(Massachusetts Institute of Technology, 2011)
Cyclization Cascades Leading to the Tricyclic Fragment of Armatol A The synthesis of the fused 6,7,7-tricycle of armatol A was investigated. Fragments containing both a ketone and an aldehyde for subsequent fragment coupling ...
Polyprenyl-dependent glycan assembly pathways in microbial pathogens
(Massachusetts Institute of Technology, 2011)
Polyisoprenyl-dependent glycan assembly pathways form the basis for the biosynthesis of many complex glycoconjugates. This thesis addresses key aspects of undecaprenyl-phosphate related processes; undecaprenol is the linear ...
Fabrication and characterization of quantum-confined optoelectronic devices based on CdSe nanocrystals
(Massachusetts Institute of Technology, 2002)
Colloidal semiconductor quantum dots (QDs), or nanocrystals (NCs), are the subject of intense research for their novel size dependent optical and electronic properties. Since the development of synthetic methods to produce ...
Synthesis and utility of electronically diverse polycyclic aromatics
(Massachusetts Institute of Technology, 2002)
This dissertation examines the synthesis of electronically diverse polycyclic aromatics within discrete molecular regimes and as incorporated into robust conjugated polymers. We have pursued two strategies for obtaining ...
Dynamics and spectra in condensed phases : single molecule spectroscopy, electron transfer, and excitation energy transfer
(Massachusetts Institute of Technology, 2002)
In this thesis, several problems regarding dynamics and spectra in condensed phases are theoretically analyzed via analytical models. The thesis consists of four main topics. First, a theoretical description of single ...
Detection and spectroscopy of single CdSe nanocrystallite quantum dots
(Massachusetts Institute of Technology, 1999)
Semiconductor nanocrystallites, with size dependent optical properties that have generated considerable interest over the past 10 years, are intrinsically difficult to study due to inhomogeneities in ensemble samples. In ...
Design and application of chiral ligands for the improvement of metal-catalyzed asymmetric transformations
(Massachusetts Institute of Technology, 1989)