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EP-4493566-B1 - COMPOUNDS FOR THE MEASUREMENT OF THE OXYGEN CONCENTRATION.

EP4493566B1EP 4493566 B1EP4493566 B1EP 4493566B1EP-4493566-B1

Inventors

  • CHEN, SIJIE
  • HO, Po Yu

Dates

Publication Date
20260513
Application Date
20230314

Claims (15)

  1. A compound according to formula (I): wherein, M is a transition metal; R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are each independently selected from the group consisting of hydrogen, halogen, optionally substituted C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, optionally substituted C 2 -C 6 alkenyl, optionally substituted C 2 -C 6 alkynyl, optionally substituted C 3-8 cycloalkyl, optionally substituted C 6 -C 14 aryl, optionally substituted heteroaryl and -N(Y) 2 ; n is 0 to 4; Y is a C 1 -C 6 alkyl, or a C 1 -C 6 haloalkyl; X is C or N; and Z is independently selected from the list consisting of S, Se, and Te.
  2. The compound according to Formula (I) as defined in Claim 1, wherein: M is Pt or Pd; R 1 and R 2 are independently selected from the group consisting of C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl and -N(Y) 2 ; R 3 is independently selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl and -N(Y) 2 ; R 4 is selected from the group consisting of C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl, halogen and -N(Y) 2 ; R 5 and R 6 are independently selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl and -N(Y) 2 ; R 7 and R 8 are independently selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl and -N(Y) 2 ; n is 0 to 4; Y is a C 1 -C 6 alkyl, or a C 1 -C 6 haloalkyl; X is C; and Z is S.
  3. The compound according to Formula (I) as defined in Claim 1 or Claim 2, wherein: M is Pt or Pd; R 1 and R 2 are independently selected from the group consisting of C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl and -N(Y) 2 ; R 3 is H; R 5 and R 6 are H; R 7 and R 8 are independently selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 6 -C 14 aryl and -N(Y) 2 ; n is 0; Y is a C 1 -C 6 alkyl, or a C 1 -C 6 haloalkyl; X is C; and Z is S.
  4. A compound as defined in any one of Claims 1 to 3, wherein the compound is according to Formula (Ia):
  5. A compound as defined in any one of Claims 1 to 3, wherein the compound is according to Formula (Ib):
  6. A process for the preparation of a compound according to Formula (I) as defined in any one of Claims 1 to 3, or a compound according to Formula (Ia) as defined in Claim 4, or a compound according to Formula (Ib) as defined in Claim 5, wherein the process comprises the steps of: (i) reacting a compound according to Formula (II) with a compound according to Formula (III) to provide a compound according to Formula (IV), wherein L represents a boronic acid or boronic ester (ii) reacting the compound according to Formula (IV) with W 2 M(R 10 ) 4 to provide a compound according to Formula (V) and (iii) reacting a compound according to Formula (V) with a compound according to Formula (VI) Wherein M, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , n, X and Z are as defined in any one of Claims 1 to 3; R 9 is a halogen; R 10 is a halogen; and W is an alkali metal.
  7. A polymeric nanoparticle loaded with a compound according to Formula (I) as defined in any one of Claims 1 to 3, or a compound according to Formula (Ia) as defined in Claim 4, or a compound according to Formula (Ib) as defined in Claim 5.
  8. The polymeric nanoparticle according to Claim 7 wherein the polymeric nanoparticle is a nanolipid carrier, such as a PEG-lipid conjugate.
  9. The polymeric nanoparticle according to Claim 8, wherein the molecular weight of the PEG in the PEG-lipid conjugate is about 1000 to about 10,000, about 1000 to about 6000, or about 2000 to about 5000.
  10. The polymeric nanoparticle according to Claim 8, wherein the lipid of the PEG-lipid conjugate is a phospholipid, such as 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE).
  11. The polymeric nanoparticle according to any one of Claims 7 to 10, wherein the compound according to Formula (I) is comprised in an amount of from about 0.1 w/w% to about 10 w/w% of the total solid content of the nanoparticle.
  12. An aqueous composition comprising a plurality of polymeric nanoparticles according to any one of Claims 7 to 11.
  13. Use of a compound according to Formula (I) as defined in any one of Claims 1 to 5, or a polymeric nanoparticle as defined in any one of Claims 7 to 11, or an aqueous composition as defined in Claim 12, for determining the concentration of oxygen in a medium.
  14. A method of measuring the concentration of oxygen in a medium comprising using a compound according to Formula (I) as defined in any one of Claims 1 to 5, or a polymeric nanoparticle as defined in any one of Claims 7 to 11, or an aqueous composition according to Claim 12.
  15. A kit-of-parts comprising; a. a solution comprising a compound according to Formula (I) as defined in any one of Claims 1 to 5, or a polymeric nanoparticle as defined in any one of Claims 7 to 11, or an aqueous composition according to Claim 12; and b. instructions for use of the kit in the method according to Claim 14.

Description

Field of Invention The present invention relates to new compounds and uses of these compounds for determining oxygen levels in a sample medium. Background and Prior Art Unlike cultured adherent cells that grow in monolayers, cells in tissues grow in three-dimensions which relies on diffusion of oxygen from the surrounding environment to interior regions (Pampaloni, F.; Reynaud, E. G.; Stelzer, E. H. K. The third dimension bridges the gap between cell culture and live tissue. Nat. Rev. Mol. Cell Biol. 2007, 8, 839-845). As such, physiological hypoxia is one of the challenges hindering tissue engineering and is associated with microenvironments in pathological conditions such as cancer and Ischemia (Semenza, Gregg L. Hypoxia-Inducible Factors in Physiology and Medicine. Cell 2012, 148, 399-408). The significance of the oxygen distribution in biology is well accepted, but not fully understood due to the lack of reliable or feasible tools for oxygen level monitoring and mapping. Nowadays, there are mainly five categories of oxygen-sensing techniques, which have been exploited to study oxygen levels in different biological systems. They are 1) polarographic electrode detection; 2) radioisotope imaging; 3) resonance imaging; 4) haemoglobin-based oxygen saturation (StO2) optical detection; and 5) luminescence-based oxygen sensing (Roussakis, E.; Li, Z.; Nichols, A. J.; Evans, C. L. Oxygen-Sensing Methods in Biomedicine from the Macroscale to the Microscale. Angew. Chem. Int. Ed. 2015, 54, 8340-8362). Polarographic electrode detection makes use of Clark electrodes to measure the electric current generated at the cathode upon voltage-driven oxygen reduction, while the oxygen partial pressure (pO2) is directly proportional to the electric current measured. However, this technique is limited to invasive point-to-point detection. Radioisotope imaging makes use of positron emission tomography (PET) scanners and intake of short-lived radiolabeled tracers to monitor oxygen metabolism rate. This technique is non-invasive, but requires the handling of hazardous radioactive species and suffers from relatively low spatial resolution. Resonance imaging exploits nuclear magnetic resonance (NMR) scanning to trace stable and non-hazardous exogenous/endogenous contrast agent(s) with respect to distinct nuclear resonance frequencies in three-dimensional space upon applying a magnetic field. This technique is non-invasive and suitable for body/organ scanning. However, the spatial resolution is rather limited. Haemoglobin-based oxygen saturation (StO2) optical detection relies on the optical absorption difference of the deoxy-/oxy-haemoglobin couple, in which the difference will reflect the blood oxygenation with the aid of a pulse oximeter. This method cannot quantify the pO2 of blood but renders StO2 of blood in a limited sensing depth (e.g. finger of human body). Luminescence-based oxygen sensing utilizes a set of optical readout devices (e.g. luminescence spectrometers and fluorescence microscopes) and oxygen-responsive luminogens. Among these methods, luminescence-based oxygen sensing is the most favorite and popular one for biological studies because of its good sensitivity, low hazard, simple operation and the possibility for high-resolution multidimensional analysis. Also, supporting facilities such as fluorescence microscopes are widely available. Luminescent indicators have, therefore, become a thresholding factor in the development of oxygen sensing/mapping technique for biological applications. Many luminescent oxygen probes have been developed for oxygen sensing. The sensing mechanisms includes oxygen-dependent reactions and luminescence quenching by oxygen (Papkovsky, D. B.; Dmitriev, R. I. Biological detection by optical oxygen sensing. Chem. Soc. Rev. 2013, 42, 8700-8732). For the reaction-based oxygen sensors, a quencher is usually linked to the sensor so that the sensor is dark in the original state. The quencher is either conjugated to the sensor through a linker (e.g. an azo bond), which undergoes oxygen-dependent cleavage by intracellular reductases, or the quencher (e.g. zwitterionic N-oxide functional group) itself is involved in an oxygen-dependent enzymatic reaction (Kiyose, K.; Hanaoka, K.; Oushiki, D.; Nakamura, T.; Kajimura, M.; Suematsu, M.; Nishimatsu, H.; Yamane, T.; Terai, T.; Hirata, Y.; Nagano, T. Hypoxia-Sensitive Fluorescent Probes for in Vivo Real-Time Fluorescence Imaging of Acute Ischemia. J. Am. Chem. Soc. 2010, 132, 15846-15848 and Xu, C.; Zou, H.; Zhao, Z.; Zhang, P.; Kwok, R. T. K.; Lam, J. W. Y.; Sung, H. H. Y.; Williams, I. D.; Tang, B. Z. A New Strategy toward "Simple" Water-Soluble AIE Probes for Hypoxia Detection. Adv. Funct. Mater. 2019, 29, 1903278). The quencher will be cleaved, or the quenching effect will be prohibited after the reduction reaction under hypoxic conditions. Therefore, these luminescent probes have a turn-on response under low oxygen conditions. Researchers have also