In this paper, we develop the theory of residually finite rationally [Formula: see text] (RFR[Formula: see text]) groups, where [Formula: see text] is a prime. We first prove a series of results about the structure of finitely generated RFR[Formula: see text] groups (either for a single prime [Formula: see text], or for infinitely many primes), including torsionfreeness, a Tits alternative, and a restriction on the BNS invariant. Furthermore, we show that many groups which occur naturally in group theory, algebraic geometry, and in 3manifold topology enjoy this residual property. We then prove a combination theorem for RFR[Formula: see text] groups, which we use to study the boundary manifolds of algebraic curves [Formula: see text] and in [Formula: see text]. We show that boundary manifolds of a large class of curves in [Formula: see text] (which includes all line arrangements) have RFR[Formula: see text] fundamental groups, whereas boundary manifolds of curves in [Formula: see text] may fail to do so.
Synthesis of highly water soluble tetrabenzoporphyrins and their application toward photodynamic therapy
Novel tetraaryl(pyridinium4yl)tetrabenzoporphyrins have been successfully synthesized via a Heckbased sequence reaction. These tetrabenzoporphyrins were substituted with eight pyridyl groups at the fused benzene rings. Methylation of the pyridyl groups with methyl iodide afforded highly water soluble tetrabenzoporphyrins carrying eight ionic groups. The extended [Formula: see text]conjugation broadened and redshifted the absorption band of these porphyrins to 650–750 nm. These cationic tetrabenzoporphyrins showed nontoxicity in the dark up to 100 uM. High phototoxicity with IC[Formula: see text] values lower than 18 [Formula: see text]M were obtained for these tetrabenzoporphyrins.
 Award ID(s):
 1800126
 Publication Date:
 NSFPAR ID:
 10159188
 Journal Name:
 Journal of Porphyrins and Phthalocyanines
 Volume:
 24
 Issue:
 01n03
 Page Range or eLocationID:
 456 to 464
 ISSN:
 10884246
 Sponsoring Org:
 National Science Foundation
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