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Dipyrrolyldiketone difluoroboron complexes (BONEPYs) reported by Maeda were mainly applied for the selective recognition of anions. Herein, innovative introduction of the ring‐fused segment in BONEPY system resulted in a twisted structure by X‐ray crystallographic analysis and enhanced the spectral bathochromic shift performance. BONEPY‐nanoparticles adjusted the energy release process of the excited state, endowed high photothermal effect, and could be degraded and discharged out of the body potentially. BONEPY‐nanoparticles are the novel phototherapeutic reagent with improved safety and low side effect. [ABSTRACT FROM AUTHOR]

1,7‐Di‐tert‐butyl‐substituted aza‐BODIPYs (tBu‐azaBDP) were successfully obtained for the first time. The structures of tBu‐azaBDP and Ph‐azaBDP were confirmed by X‐ray crystal analysis, and tBu‐azaBDP 2 is more twisted than Ph‐azaBDP 5. tBu‐azaBDPs have significant photo‐stability and enhanced water solubility. tBu‐azaBDPs possess excellent optical properties, such as high molar extinction coefficients, broad full width half maxima, and large Stokes shifts, which is comparable to those of the parent dye Ph‐azaBDP. Although the low‐barrier rotation of the distal ‐tBu groups in tBu‐azaBDPs results in low quantum yield, photothermal conversion efficiency and singlet oxygen generation ability of tBu‐azaBDPs are more effective than those of Ph‐azaBDP, which is highly desirable for a photothermal‐photodynamic therapy agent. [ABSTRACT FROM AUTHOR]

Ring-fused quinoid-bisboron pyrrole dyes with double BF 2 chelation (QBBP) were prepared for the first time. According to X-ray crystallographic analysis, the centrosymmetric structure of QBBP was confirmed. The core of the central quinone moiety and two ring-fused pyrroles is almost planar, and the arrangement of aggregates involve J -type packing. Bisboron dye QBBP underwent two successive one-electron reduction and two successive one-electron oxidation processes. QBBP absorbs in the near-infrared (NIR) with a high molar extinction coefficient. Although QBBP shows no fluorescence and low intersystem crossing (ISC) efficiency, it has considerable photothermal conversion efficiency and is desirable for a photothermal-photodynamic therapy agent. [Display omitted] • Ring-fused quinoid-bisboron pyrrole dyes with double BF 2 chelation (QBBP) were prepared for the first time. • The centrosymmetric structure of QBBP was confirmed and the arrangement of aggregate is J -type packing. • QBBP underwent two successive one-electron reduction and two successive one-electron oxidation processes. • QBBP absorbs in the NIR and has a high molar extinction coefficient. • QBBP has a considerable photothermal conversion efficiency. [ABSTRACT FROM AUTHOR]

Novel vinyl-containing pyrroles were developed by the reaction of vinyl-containing ketones with 3-phenyl-2H-azirine in the presence of LDA. Utilizing these pyrroles, asymmetric vinyl-containing azaBDPs 1 – 8 were prepared, avoiding to the use of Knoevenagel condensation. Solid-state structure of 7 was confirmed by X-ray crystallographic analysis, and the furan, the vinyl group and the pyrrole segment in 7 are almost coplanar, owing to the conjugation. AzaBDPs 1 – 8 absorb and emit beyond 685 nm, and have low fluorescence quantum yields. AzaBDPs 1 – 8 were found to merely possess the 1O 2 production capacity. The formed azaBDP nanoparticles (7 -NPs) by facile encapsulation of F127 exhibit the excellent photothermal stabilities. Noteworthily, 7 -NPs show the outstanding photothermal conversion efficiency (η = 55%) in aza-BODIPY system, and can effectively kill cancer cells through the photothermal conversion, which is highly desirable for an effective and potential tumor phototherapeutic reagent. [Display omitted] • Asymmetric vinyl-containing azaBDPs 1 – 8 were prepared, avoiding to the use of Knoevenagel condensation. • The furan, the vinyl group and the pyrrole segment in 7 are almost coplanar, based on X-ray crystallographic analysis. • 7 -NPs show the outstanding photothermal conversion efficiency (η = 55%) in aza-BODIPY system. • 7 -NPs can effectively kill cancer cells through the photothermal conversion. [ABSTRACT FROM AUTHOR]

Photothermal therapy in the treatment of malignant tumors had attracted extensive attention owing to unique non-invasive and low-toxicity characteristics. Herein, aza-BDOIPY scaffold (NEt-azaBDP) was employed to construct a novel molecule using the duplex design strategies of diethylamino substitute and tert -butyl introduction. Self-assembly NEt-azaBDP nanoparticles (NEt-azaBDP NPs) had no fluorescence but produced heat energy via non-radiative transition, owing to the combination of the intramolecular charge transfer (ICT) by diethylamino groups and the free rotation tert -butyl segment. The photothermal conversion efficiency can reach 51.2 % under light irradiation. NEt-azaBDP NPs effectively kill glioma cells when exposed to light, and significantly impede the migratory and proliferation of gliomas. The observed therapeutic effects are attributed to the impairment of mitochondria in gliomas based on mitochondrial bioenergetic analysis. This provides a good strategy for the design of NEt-azaBDP NPs with the potent photothermal therapeutic effects which augur well for the prospective clinical applications for gliomas. [Display omitted] • aza-BDOIPY scaffold (NEt-azaBDP) was constructed by the duplex design strategies of diethylamino substitute and tert -butyl introduction. • Self-assembly NEt-azaBDP nanoparticles produced heat energy, owing to the combination of the intramolecular charge transfer by diethylamino groups and the free rotation tert -butyl segments. • NEt-azaBDP NPs effectively kill glioma cells when exposed to light, and significantly impede the migratory and proliferation of gliomas. [ABSTRACT FROM AUTHOR]

Asymmetric mono - and dibromides aza-BODIPYs at 6-site were prepared. The singlet oxygen yield of monobromide MBr-azaBDP with the direct attachment of the –Br group at 6-site was higher than that of vinyl dibromide DBr-azaBDP. Self-assembled MBr-azaBDP -NPs with laser irradiation possessed a photothermal conversion capability. Monobromide MBr-azaBDP was discovered to be an effective PDT-PTT combined therapeutic agent and prospective candidate for tumor phototherapy by integrating tert -butyl free rotation and halogen substitution. However, comparing to MBr-azaBDP , DBr-azaBDP as a fluorescent dye possesses narrower full width at half maxima, higher molar extinction coefficient and fluorescence quantum yield. [Display omitted] • Asymmetric mono- and dibromides aza-BODIPYs at 6-site were prepared. • Singlet oxygen yield of MBr-azaBDP was higher than that of vinyl dibromide DBr-azaBDP. • Self-assembled MBr-azaBDP -NPs with laser irradiation possessed a photothermal conversion capability. • DBr-azaBDP as a fluorescent dye has narrow full width at half maxima, high molar extinction coefficient and fluorescence quantum yield. [ABSTRACT FROM AUTHOR]

The thermogenesis process is enhanced by the accelerated non-radiative transition energy dissipation induced by the free rotation of the –CF 3 group at meso -site in BODIPY system, which is a valuable strategy for tumor photothermal therapy. In this work, we first introduced the diene bonds to meso -CF 3 -BODIPY at 3,5-sites. This diene-extended meso -CF 3 -BODIPY possessed remarkable photostability with a near-infrared absorption (λ a b s = 836 nm), and the fluorescence emission and triplet transition are both inhibited. meso -CF 3 -BODIPY-NPs by self-assembly has a photothermal conversion efficiency (PCE: 44.4%) and good promotion of cancer cell apoptosis upon irradiation. Therefore, this molecular design performed as a critical reference for the construction of forthcoming photothermal reagents. • The diene bonds were introduced to meso -CF 3 -BODIPY at 3,5-sites. • This diene-extended meso -CF 3 -BODIPY possessed near-infrared absorption (λ a b s = 836 nm). • meso -CF 3 -BODIPY-NPs by self-assembly had a photothermal conversion efficiency (PCE: 44.4%) and could kill cancer cells via apoptosis upon irradiation. [ABSTRACT FROM AUTHOR]

Using 1-(4-(dimethylamino)phenyl)ethanone, a series of asymmetric aza-BODIPYs carrying the dimethylamino (–NMe 2) group were successfully prepared (Scheme 1). The solid-state structure of trifluoromethyl substituted aza-BODIPY (CF 3 -BDP) was confirmed by X-ray crystallographic analysis, and the boron atom in the center showed a slightly distorted sp 3 hybridization. The maxima absorption of aza-BODIPYs with the –NMe 2 group were found to locate in the range of 740–780 nm. Their molar extinction coefficients are high, but the fluorescence quantum yields are very low, mainly due to the intramolecular charge transfer (ICT) effect from the −NMe 2 group to aza-BODIPY scaffold. The singlet oxygen yields of CF 3 -BDP was calculated to be 0.053 and slightly higher than that (Φ Δ = 0.02) of tetraphenyl aza-BODIPY. In order to improve water-solubility and biocompatibility, we prepared dye nanoparticles by self-assembly. Based on the photothermal properties of CF 3 - BDP nanoparticles (NPs), methoxy substituted aza-BODIPY (OMe-BDP) NPs and ring-fused substituted aza-BODIPY (OMeR-BDP) NPs, the photothermal conversion efficiencies of CF 3 -BDP NPs, OMe-BDP NPs and OMeR-BDP NPs were calculated to be 49%, 49% and 50%, which are comparable to those (35–50.5%) of the reported aza-BODIPY-based photothermal agents (PTAs). CF 3 -BDP NPs could efficiently kill cancer cells through the photothermal effect by near-infrared laser irradiation, and CF 3 -BDP NPs are highly desirable for the photothermal therapy. [Display omitted] • A series of asymmetric aza-BODIPYs bearing the –NMe 2 group were prepared by N,N-dimethyl-4-(4-phenyl-1H-pyrrol-2-yl)aniline. • Photothermal conversion efficiency of CF 3 -BDP NPs was calculated to be 49%. • CF 3 -BDP NPs could efficiently kill cancer cells through the photothermal effect. [ABSTRACT FROM AUTHOR]