@article{yao_borbas_lindsey_2008, title={Soluble precipitable porphyrins for use in targeted molecular brachytherapy}, volume={32}, ISSN={["1369-9261"]}, DOI={10.1039/b714127k}, abstractNote={In a new therapy that aims to concentrate and immobilize therapeutic radionuclides in nanoscale assemblies within solid tumors, a soluble precipitable reagent (SPR) is administered as the radionuclide carrier and is converted to non-diffusible precipitate by an enzyme located in tumor tissues. To meet the objective of such an SPR, we have prepared and examined a class of porphyrin–alkyldiphosphates that are soluble in aqueous solution and that are rendered insoluble upon removal of the two phosphate groups. The porphyrins examined herein are of the trans-AB architecture wherein the substituents are a bis(dihydroxyphosphoryloxy)alkyl group and a phenyl (or p-bromophenyl) group. Provisions for later incorporation of radionuclides have been established by preparation of the analogous copper chelate or the meso-iodo free-base porphyrin. Altogether, four porphyrins bearing a bis(dihydroxyphosphoryloxy)alkyl group were examined and found to exhibit satisfactory solubility in water (>1 mM). Dephosphorylation reactions have been carried out in vitro using the enzyme shrimp alkaline phosphatase. In each case, enzyme-induced precipitation was observed. The soluble-to-insoluble conversion has been examined by visual inspection, absorption spectroscopy, electrospray ionization mass spectrometry, and nephelometry using non-radiolabeled porphyrins.}, number={3}, journal={NEW JOURNAL OF CHEMISTRY}, author={Yao, Zhen and Borbas, K. Eszter and Lindsey, Jonathan S.}, year={2008}, pages={436–451} }
 @article{ptaszek_yao_savithri_boyle_lindsey_2007, title={Synthesis and structural properties of porphyrin analogues of bacteriochlorophyll c}, volume={63}, ISSN={["0040-4020"]}, DOI={10.1016/j.tet.2007.10.023}, abstractNote={The self-assembling photosynthetic pigment bacteriochlorophyll c contains α-hydroxyethyl and keto groups on opposite sides of the macrocycle. A porphyrin has been synthesized that contains a 3-hydroxymethyl group and a 15-ethoxycarbonyl group (ZnP2-OH). X-ray analysis of ZnP2-OH and the related porphyrin containing 5-hydroxymethyl and 15-ethoxycarbonyl groups (ZnP1-OH) in each case revealed infinite coordination polymers wherein the zinc porphyrins are bound by Zn–O coordination and are cofacially offset in a staircase architecture.}, number={51}, journal={TETRAHEDRON}, author={Ptaszek, Marcin and Yao, Zhen and Savithri, Dhanalekshmi and Boyle, Paul D. and Lindsey, Jonathan S.}, year={2007}, month={Dec}, pages={12629–12638} }
 @article{yao_bhaumik_dhanalekshmi_ptaszek_rodriguez_lindsey_2007, title={Synthesis of porphyrins bearing 1-4 hydroxymethyl groups and other one-carbon oxygenic substituents in distinct patterns}, volume={63}, ISSN={["0040-4020"]}, DOI={10.1016/j.tet.2007.07.108}, abstractNote={Porphyrins that bear one-carbon oxygenic substituents (hydroxymethyl, formyl, ester) directly attached to the macrocycle afford a compact architecture of utility for diverse applications. Routes to 9 porphyrins bearing such groups in distinct architectures (A4-, trans-A2-, trans-A2B2-, trans-AB-, and trans-AB2C-porphyrins) have been explored (A=hydroxymethyl), including porphyrins bearing two one-carbon units in different oxidation states (hydroxymethyl/ester, formyl/ester). The hydroxymethyl group was introduced via TBDMS-protected dipyrromethane precursors.}, number={43}, journal={TETRAHEDRON}, author={Yao, Zhen and Bhaumik, Jayeeta and Dhanalekshmi, Savithri and Ptaszek, Marcin and Rodriguez, Phillip A. and Lindsey, Jonathan S.}, year={2007}, month={Oct}, pages={10657–10670} }
 @article{bhaumik_yao_borbas_taniguchi_lindsey_2006, title={Masked imidazolyl-dipyrromethanes in the synthesis of imidazole-substituted porphyrins}, volume={71}, ISSN={["0022-3263"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-33750879603&partnerID=MN8TOARS}, DOI={10.1021/jo061461r}, abstractNote={Imidazole-substituted metalloporphyrins are valuable for studies of self-assembly and for applications where water solubility is required. Rational syntheses of porphyrins bearing one or two imidazol-2-yl or imidazol-4-yl groups at the meso positions have been developed. The syntheses employ dipyrromethanes, 1-acyldipyrromethanes, and 1,9-diacyldipyrromethanes bearing an imidazole group at the 5-position. The polar, reactive imidazole unit was successfully masked by use of (1) the 2-(trimethylsilyl)ethoxymethyl (SEM) group at the imidazole pyrrolic nitrogen, and (2) a dialkylboron motif bound to the pyrrole of the dipyrromethane and coordinated to the imidazole imino nitrogen. The nonpolar nature of such doubly masked imidazolyl-dipyrromethanes facilitated handling. Selected masked dipyrromethanes were characterized by 11B and 15N NMR spectroscopy. Five distinct methods were examined to obtain trans-A2B2-, trans-AB2C-, and trans-AB-porphyrins. Each porphyrin contained one or two SEM-protected imidazole units. The SEM group could be removed with TBAF or HCl. Two zinc(II) porphyrins and a palladium(II) porphyrin bearing a single imidazole moiety were prepared and subjected to alkylation (with ethyl iodide, 1,3-propane sultone, or 1,4-butane sultone) to give water-soluble imidazolium- porphyrins. This work establishes the foundation for the rational synthesis of a variety of porphyrins containing imidazole units.}, number={23}, journal={JOURNAL OF ORGANIC CHEMISTRY}, publisher={American Chemical Society (ACS)}, author={Bhaumik, Jayeeta and Yao, Zhen and Borbas, K. Eszter and Taniguchi, Masahiko and Lindsey, Jonathan S.}, year={2006}, month={Nov}, pages={8807–8817} }
 @article{fan_taniguchi_yao_dhanalekshmi_lindsey_2005, title={1,9-bis(N,N-dimethylaminomethyl)dipyrromethanes in the synthesis of porphyrins bearing one or two meso substituents}, volume={61}, ISSN={["0040-4020"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-25144489698&partnerID=MN8TOARS}, DOI={10.1016/j.tet.2005.08.028}, abstractNote={A synthesis of 5,15-disubstituted zinc-porphyrins has been developed that employs condensation of a 1,9-bis(N,N-dimethylaminomethyl)dipyrromethane+a dipyrromethane in refluxing ethanol containing zinc acetate followed by oxidation with DDQ. The N,N-dimethylaminomethylation of the dipyrromethane was achieved via Eschenmoser's reagent (N,N-dimethylmethyleneammonium iodide) in CH2Cl2 at room temperature. The synthesis is compatible with diverse substituents (e.g., alkyl, aryl, ester, acetal) and enables rapid synthesis of trans-AB-, A2-, and A-porphyrins. The synthesis of >40 zinc porphyrins has been surveyed; 13 zinc porphyrins were isolated in yields of 5–20% without detectable scrambling.}, number={43}, journal={TETRAHEDRON}, publisher={Elsevier BV}, author={Fan, DZ and Taniguchi, M and Yao, Z and Dhanalekshmi, S and Lindsey, JS}, year={2005}, month={Oct}, pages={10291–10302} }