Quantitative Structure-Activity Relationship Analysis of Natural Products: Phototoxic Thiophenes

Structure‐activity Studies of Photoactivated Antiviral and Cytotoxic Tricyclic Thiophenes

“…Calculated octanol/water partition coefficients and CMR values were calculated using the MedChem Software package (version 3.54, Daylight Chemical Information Systerns, Inc., Claremont, CA). Good agreement between calculated CLOGP and observed log P values for thiophenes has been reported previously (Marles et al, 1991a). Regression analyses were performed using the QSAR program (Pomona College, Claremont, CA).…”

“…Some specificity of thiophene analogues against particular organisms was observed. Quantitative structure-activity relationship (QSAR) analysis has been applied to light-mediated and dark toxicities of tricyclic thiophenes with potential as vector-control agents against mosquito larvae and against a nontarget species, brine shrimp nauplii (Marles et al, 1991a(Marles et al, , 1991b. These studies revealed that the phototoxic effects were significantly correlated with hydrophobicity and rate of 02(lA ) roduction, and suggested the possibility of achieving species selectivity by manipulation of the physicochemical properties of the molecule.…”

Design, Synthesis, Linear, and Nonlinear Optical Properties of Conjugated (Porphinato)zinc(II)-Based Donor−Acceptor Chromophores Featuring Nitrothiophenyl and Nitrooligothiophenyl Electron-Accepting Moieties

“…Oligothiophenes bearing electron-releasing or -accepting groups , have featured in structures that probe intramolecular electronic and energy transfer reactions 44,46 as well as an extensive family of hyperpolarizable chromophores. ,− Studies that examined the impact of terminal oligothiophene substituents on electrochemical and optical properties 35 demonstrate that nitro functionality drives bathochromic shifts of the S 0 → S n electronic transitions, large emission band Stokes shifts, and substantial solvatochromism. While these terminally nitro-substituted oligothiophenes have previously been synthesized and examined mainly for their potential utility as phototoxic agents, − their electronic structural properties suggest that such conjugated oligothiophenes may find utility in driving preferential excited-state electronic redistributions within a hyperpolarizable push−pull ethynylporphyrin structural motif. , …”

“…16,[22][23][24][25][26][27][28][29][30][31][32][33][34] Studies that examined the impact of terminal oligothiophene substituents on electrochemical and optical properties 35 demonstrate that nitro functionality drives bathochromic shifts of the S 0 f S n electronic transitions, large emission band Stokes shifts, and substantial solvatochromism. While these terminally nitro-substituted oligothiophenes have previously been synthesized and examined mainly for their potential utility as phototoxic agents, [57][58][59][60][61] their electronic structural properties suggest that such conjugated oligothiophenes may find utility in driving preferential excitedstate electronic redistributions within a hyperpolarizable pushpull ethynylporphyrin structural motif. Scheme 1 shows the synthetic route utilized to fabricate terminally nitro-substituted thiophene and oligothiophene moieties having reactive iodo or ethynyl functionality that enable facile conjugation to the porphyrin meso-carbon position.…”