Syntheses of Cannabinoid Metabolites: Ajulemic Acid and HU-210.

Cannabinoid metabolites have been reported to be more potent than their parent compounds. Among them, ajulemic acid (AJA) is a side-chain analog of Δ9-THC-11-oic acid, which would be a good template structure for the discovery of more potent analogues. Herein, we optimized the key allylic oxidation step to introduce the C-11 hydroxy group with a high yield. A series of compounds was prepared with this condition applied including HU-210, 11-nor-Δ8-tetrahydrocannabinol (THC)-carboxylic acid and Δ9-THC-carboxylic acid.

The Synthesis of Biphasic Metabolites of Carfentanil.

Carfentanil is an ultra-potent synthetic opioid. The Russian police force used both carfentanil and remifentanil to resolve a hostage incident in Moscow. This reported use sparked an interest in the pharmacology and toxicology of carfentanil in the human body, and data on its metabolites were later published. However, there have been few studies on the synthesis of carfentanil metabolites, and biological extraction has also put forward large uncertainty in subsequent studies. The aim of the present study is to investigate the synthesis of biphasic metabolites that are unique to carfentanil. The purpose was to produce corresponding metabolites conveniently, quickly, and at low cost that can be used for comparison with published structures and to confirm the administration of carfentanil.

Synthesis of 2-morpholinetetraphenylporphyrins and their photodynamic activities.

A series of 2-morpholinetetraphenylporphyrins functionalized with various substituents (Cl, Me, MeO group) at 4-phenyl position were prepared via nucleophilic substitution of 2-nitroporphyrin copper derivatives with morpholine by refluxing under a nitrogen atmosphere and then demetalization. Their basic photophysical properties, intracellular localization, cytotoxicities in vitro and in vivo were also investigated. All synthesized photosensitizers exhibited longer maxima absorption wavelengths than Hematoporphyrin monomethyl ether (HMME). They showed low dark cytotoxicity compared with that of HMME and were more phototoxic than HMME against Eca-109 cells in vitro. M3 also exhibited better photodynamic antitumor efficacy on BALB/c nude mice at a lower concentration. Therefore, M3 is a promising antitumor photosensitizer in photodynamic therapy application.

Synthesis and antitumor activity evaluation of a novel porphyrin derivative for photodynamic therapy in vitro and in vivo.

A novel porphyrin derivative, 5, 10, 15, 20-tetrakis (5-morpholinopentyl)-21H, 23H-Porphin (MPP, 4) and its photophysical characteristics, therapeutic efficacy of photodynamic therapy (PDT) in vitro and in vivo, tumor selectivity, and clearance from normal tissues were investigated here. MPP has strong absorption at relatively long wavelength (λmax = 648 nm, molar absorption coefficient ε ∼ 17,200 M(-1)cm(-1)) and can emit strong fluorescence at 653 and 718 nm. When administered to the animal tumor models by tail vein injection, MPP was capable of accumulating in the tumor site, as examined in vivo with the fluorescence signal of MPP. By the combination of MPP and a 650-nm laser irradiation, the viability of T24 cells could decrease by 4.37 %, and inhibition rate of T24 tumor could increase up to 91.21 % compared with control group, demonstrating the potential of MPP as an effective photosensitizer in PDT for tumor treatment.

Synthesis, photophysical properties and biological evaluation of ß-alkylaminoporphyrin for photodynamic therapy.

A series of ß-alkylaminoporphyrins conjugated with different amines at ß position (D1-D3) or with electron-donating and electron-withdrawing substituents at phenyl position (D4-D6) were synthesized. Their photophysical and photochemical properties, intracellular localization, photocytotoxicities in vitro and vivo were also investigated. All target compounds exhibited no cytotoxicities in the dark and excellent photocytotoxicities against HeLa cells. Among them, D6 showed the highest phototoxicity and the lowest dark toxicity, which was more phototoxic than Hematoporphyrin monomethyl ether (HMME). In addition, D6 exhibited best photodynamic antitumor efficacy on BALB/c nude mice bearing HeLa tumor. Therefore, D6 is a powerful and promising antitumor photosensitizer for photodynamic therapy.

Design, synthesis, and pharmacological evaluation of 5-oxo-1,2,4-oxadiazole derivatives as AT1 antagonists with antihypertension activities.

A series of new 5-oxo-1,2,4-oxadiazole derivatives with 1, 4-disubsituted or 1, 5-disubsituted indole group was designed, synthesized, and pharmacologically evaluated. These derivatives displayed high affinities to the AT1 receptor at the same order of magnitude to losartan. The methyl ester with 1, 4-disubsituted indole group, 1 (5.01 ± 1.67 nM) showed high antihypertension activity on spontaneously hypertensive rats (SHRs). Its maximal response lowered 30 mmHg of mean blood pressure (MBP) at 10 mg/kg after oral administration, which was better than irbesartan, and the antihypertensive effect lasted beyond 24 h. These results made 1 deserve further investigation.

Synthesis, structural characterization, analytical profiling, and application to authentic samples of synthesized Phase I metabolites of the synthetic cannabinoid 5F-MDMB-PICA.

5F-MDMB-PICA, an indole-type synthetic cannabinoid (SC), was classified illicit globally in 2020. Although the extensive metabolism of 5F-MDMB-PICA in the human body warrants the development of robust analytical methods for metabolite detection and quantification, a current lack of reference standards for characteristic metabolites hinders such method creation. This work described the synthesis of 18 reference standards for 5F-MDMB-PICA and its possible Phase I metabolites, including three hydroxylated positional isomers R14 to R16. All the compounds were systematic characterized via nuclear magnetic resonance, Fourier transform infrared spectroscopy, and high-resolution mass spectrometry. Furthermore, two methods were developed for the simultaneous detection of all standards using liquid chromatography-tandem mass spectrometry and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. By comparison with authentic samples, R17 was identified as a suitable urine biomarker for 5F-MDMB-PICA uptake.

Comparison between porphin, chlorin and bacteriochlorin derivatives for photodynamic therapy: Synthesis, photophysical properties, and biological activity.

The development of novel photosensitizers is a challenging task for photodynamic therapy (PDT). Twelve novel photosensitizers (PSs), including porphins (P1-4), chlorins (C1-4) and bacteriochlorins (B1-4) were synthesized. The bacteriochlorins exhibited the longest absorption wavelength (λmax = 736 nm), which is higher than that of porphins (λmax = 630 nm) and chlorins (λmax = 644 nm). In vitro photodynamic activities on Eca-109 human esophageal carcinoma cells were evaluated by standard assays and all PSs showed photodynamic activity. Among them, B2 displayed the highest phototoxicity and the lowest dark toxicity. In addition, B2 exhibited best photodynamic antitumor efficacy on BALB/c nude mice bearing Eca-109 cells tumor. Therefore, B2 is a powerful and promising antitumor photosensitizer for PDT.

Tetraphenylporphyrin derivatives possessing piperidine group as potential agents for photodynamic therapy.

Photodynamic therapy (PDT) is a noninvasive therapeutic and promising procedure in cancer treatment and has attracted considerable attention in recent years. In the present paper, 2-piperidinetetraphenylporphyrin derivatives (P1-P3) conjugated with different substituents (Cl, Me, MeO group) at phenyl position were synthesized via nucleophilic substitution of 2-nitroporphyrin copper derivatives with piperidine by refluxing under a nitrogen atmosphere and then demetalization. The combination of 1H NMR, 13C NMR and HR-MS was used to elucidate the identities of them. Their photophysical and photochemical properties, intracellular localization, cytotoxicity in vitro and in vivo against QBC-939 cells were investigated. They have absorption at wavelength about 650nm. All synthesized photosensitizers showed low dark cytotoxicity and comparable with that of hematoporphyrin monomethyl ether (HMME). And they were more phototoxic than HMME to QBC-939 cells in vitro. In bearing QBC-939 tumor BALB/c nude mice, when it treated with 5mg/kg dose of PS and laser light (650nm, 100J/cm2, 180mW/cm2), the growth of tumor was inhibited compared to the control group. Among them, P3 exhibited better photodynamic antitumor efficacy on BALB/c nude mice at lower concentration. These results indicate that P3 is a new potential antitumor photosensitizer in photodynamic therapy and deserves further investigation.

Antitumor activity evaluation of meso-tetra (pyrrolidine substituted) pentylporphin-mediated photodynamic therapy in vitro and in vivo.

Photodynamic therapy is a minimally invasive and promising new method in cancer treatment and has attracted considerable attention in recent years. An ideal photosensitizer is a crucial element to photodynamic therapy. In the present paper, a novel porphyrin derivative, 5, 10, 15, 20-tetrakis (5-(pyrrolidin-1-yl) pentyl) porphin (TPPP) was synthesized. Its spectroscopic and physicochemical properties, therapeutic efficacy as a photosensitizer in photodynamic therapy for human bladder cancer in vitro and in vivo were investigated. TPPP had strong absorption at 648nm (ε=1.75×10(4)M(-1)cm(-1)), and two fluorescence emission peaks at 652nm and 718nm. PDT with TPPP showed low dark toxicity and high phototoxicity to human bladder cancer T24 cells in vitro. In bearing T24 tumor nude mice, the growth of tumor was significantly inhibited by combining use of 5mg/kg TPPP with 100J/cm(2) (650nm, 180mW/cm(2)) laser irradiation at 3h following injection of TPPP. The antitumor effect was also confirmed with histopathological assay. The histopathological study results revealed that PDT using TPPP and 100J/cm(2) (650nm, 180mW/cm(2)) laser irradiation induced tumor cells shrunken and necrotic. These results indicate that TPPP is useful as a new photosensitizer in PDT for cancer, and deserves further investigation.