Synthesis and Characterization of Three Novel Amphiphilic Aminated Hypocrellins as Photodynamic Therapeutic Agents¶

Abstract

To improve the amphiphilicities and red absorption of the hypocrellins, three novel 2-amino-2-demethoxy-hypocrellins were synthesized by the mild reactions of hypocrellin B with 4-(2-amino-ethyl)morpholine, N,N-dimethylethylenediamine and 1-(2-amino-ethyl)piperazine, respectively. The structures of these derivatives were characterized with proton nuclear magnetic resonance, infrared and mass spectra (MS). The ultraviolet-visible absorption and fluorescence spectra of the derivatives were measured and the new amino-substituted hypocrellins showed strong absorption in the domain of the phototherapeutic window (600-900 nm). Their amphiphilicities evaluated via the partition coefficients between n-octanol and phosphate-buffered saline buffer improved remarkably. Electron paramagnetic resonance spin-trapping measurements were used to investigate the photodynamic action of the three compounds in the presence of oxygen. Singlet oxygen (1O2) and superoxide anion radical (O2.-) generated by illuminating the hypocrellin derivatives in aerobic solution were observed.

Near‐Infrared Hypocrellin Derivatives for Synergistic Photodynamic and Photothermal Therapy

“…[25,[30][31][32][33][34][35][36] Different chemical modifications on HB induce variations in absorption properties and 1 O 2 yields. [37][38][39][40][41][42] Amino-substituted HB derivatives at position 2 could remarkably enhance longerwavelength absorption bands near 600 nm compared with that of HB (Scheme 1). Substitution on the carbonyl groups (position 3 or 4, Scheme 1) of HB could distinctly red-shifted the absorption wavelength longer than 600 nm.…”

Smart Aza-BODIPY Photosensitizer for Tumor Microenvironment-Enhanced Cancer Phototherapy

“…Herein, an aza-BODIPY-derived organic photosensitizer MAB with morpholine decorated at the periphery site is synthesized to give strong NIR absorption and high pH sensitivity (Scheme ). Such a structure favors the photoinduced electron transfer (PET) process, which will be quenched by a proton under weak acidic TME, along with amplified fluorescence and fortified photothermal conversion efficiency as well as increased ROS generation. , Water-soluble MAB nanoparticles (NPs) with great biocompatibility are obtained through enwrapping MAB molecules with amphiphilic DSPE-mPEG 2000 .…”

Synthesis and photodynamic activity of new imidazole substituted pyropheophorbide-a derivatives

“…Many photosensitizers have been reported or clinically used [4,5], but most of them have limitations such as low photostability, diffi culty in purifi cation, low red absorption, structural instability and severe persistent photosensitizing side effects [6,7]. Although exact mechanism of PDT in cancer treatment is still unknown [8,9], there is a scope for exploring new variations to amplify the therapeutic effi cacy of photosensitizers [10,11].…”