Liquids with High Compressibility

Compressibility is a fundamental property of all materials. For fluids, that is, gases and liquids, compressibility forms the basis of technologies such as pneumatics and hydraulics and determines basic phenomena such as the propagation of sound and shock waves. In contrast to gases, liquids are almost incompressible. If the compressibility of liquids could be increased and controlled, new applications in hydraulics and shock absorption could result. Here, it is shown that dispersing hydrophobic porous particles into water gives aqueous suspensions with much greater compressibilities than any normal liquids such as water (specifically, up to 20 times greater over certain pressure ranges). The increased compressibility results from water molecules being forced into the hydrophobic pores of the particles under applied pressure. The degree of compression can be controlled by varying the amount of porous particles added. Also, the pressure range of compression can be reduced by adding methanol or increased by adding salt. In all cases, the liquids expand back to their original volume when the applied pressure is released. The approach shown here is simple and economical and could potentially be scaled up to give large amounts of highly compressible liquids.

Type 3 Porous Liquids for the Separation of Ethane and Ethene

We assess the potential for formulating a porous liquid that could be used as a selective solvent for the separation of ethane and ethene. Ethane-ethene separation is performed on very large scales by cryogenic distillation, but this uses large amounts of energy. Solvents that are selective to ethane or ethene could potentially enable more efficient liquid-based separation processes to be developed, but to date such solvents have been elusive. Here, Type 3 porous liquids, which consist of microporous solids dispersed in size-excluded liquid phases, were tailored toward the separation of ethane and ethene. A high selectivity for ethene over ethane (25.6 at 0.8 bar) and a high capacity was achieved for zeolite AgA dispersed in an Ag-containing ionic liquid. Unusually for liquid phases, the selectivity for ethane over ethene (2.55 at 0.8 bar) could also be achieved using either the metal-organic framework (MOF) Cu(Qc)₂ (Qc = quinoline-5-carboxylate) dispersed in sesame oil or ZIF-7 in sesame oil, the latter showing gated uptake. The efficiency of the Cu(Qc)₂ synthesis was increased by developing a mechanochemical method. The regeneration of Cu(Qc)₂ in sesame oil and ZIF-7 in sesame oil was also demonstrated, suggesting that these or similar porous liquids could potentially be applied in cyclic separation processes.

In vitro Activity of a Novel Series of Polyoxosilicotungstates against Human Myxo-, Herpes- and Retroviruses

A series of silicon-containing polyoxotungstates belonging to the ‘Keggin-type’ (‘Keggin’, ‘Keggin sandwich’) were evaluated for their antiviral activity against enveloped viruses (myxo-, herpes- and retroviruses). The compounds exhibited antiviral activity against influenza virus type A, respiratory syncytial virus (RSV), herpes simplex virus type-1 (HSV-1), type-2 (HSV-2), thymidine kinase-deficient (TIC) HSV-1, human cytomegalovirus (HCMV), human immunodeficiency virus type-1 (HIV-1) and type-2 (HIV-2) at concentrations that were well below their cytotoxic threshold. The ‘Keggin’ compound JM2815 (K5[Si-(TiCp)W11O39].12H2O) and the ‘Keggin sandwich’ compound JM1590 (K13[Ce(SiW11O39)2].26H2O) resulted in the highest selectivity indices against HIV-1 and HIV-2, and compound JM2820 ([Me3NH]8.[Si2Nb6W18O77]) was the most potent inhibitor of HSV and HCMV replication. These compounds proved active against HCMV and HSV when present during virus adsorption, and against influenza virus A and RSV when present after virus adsorption. Polyoxosilicotungstates inhibited the binding of radiolabeled HCMV particles to the cells at concentrations that were antivirally active, and the compounds were able to displace HCMV particles that were bound to a heparin-Sepharose matrix. Presumably, the polyoxosilicotungstates interact with positively charged domains on the viral envelope site(s) involved in the attachment of the (HCMV) virions to the cell surface receptor heparan sulphate.

Antitumor-activity of orally-administered ammine amine platinum (iv) dicarboxylate complexes against a panel of human ovarian-carcinoma xenografts

The antitumour activity of a series of ten novel ammine/amine platinum (IV) dicarboxylates of general formula [Pt(IV) Cl2 (OCOR1) NH3 (RNH2)] where R1 was an aliphatic or aromatic substituent and R an aliphatic or alicyclic substituent, was evaluated, after oral administration, to nude mice bearing various human ovarian carcinoma xenografts. The tumours were chosen to encompass a wide range in responsiveness to the clinically used platinum-based drugs cisplatin and carboplatin, with tumour growth delays varying from less than 10 days to greater than 60 days. Against two tumour lines, the platinum (IV) ammine/amine dicarboxylate JM221 (R1=C3H7; R= cC6H11) exhibited similar antitumour activity whether administered by the oral or intraperitoneal route. Experiments have been performed using four xenografts to provide a direct comparison of the antitumour effects of three platinum (IV) ammine/amine butyrates (JM216, R=cC6H11; JM225, R=cC5H9; JM269, R=cC7H13; R1=C3H7 for all three) administered by the oral route versus cisplatin and carboplatin administered by the intravenous route at equitoxic q7dx4 schedules. All three dicarboxylates exhibited oral activity broadly comparable to cisplatin and carboplatin and significantly superior to tetraplatin (Ormaplatin; a 1,2 diaminocyclohexane-containing platinum drug currently undergoing clinical evaluation). Average specific growth delay values across the four xenografted lines were 3.45 for cisplatin, 3.9 for carboplatin, 3.2 for JM216, 3.3 for JM225, 3 for JM269 and only 0.55 for tetraplatin. Thus the ammine/amine platinum (IV) dicarboxylates represent a novel class of platinum drug for oral administration capable of exhibiting broadly comparable activity to cisplatin and carboplatin in a panel of human ovarian carcinoma xenografts.

Phase I and pharmacokinetic study of an oral platinum complex given daily for 5 days in patients with cancer

PURPOSE

We aimed to determine the maximum-tolerated dose (MTD) clinical toxicities, pharmacokinetics, and pharmacodynamics of oral JM216 given once daily for 5 days to cancer patients.

PATIENTS AND METHODS

Patients who fulfilled standard phase I trial criteria were enrolled. Oral JM216 was given at doses based on patient body-surface area, on an empty stomach, once daily for 5 consecutive days, as 10-, 50-, and 200-mg hard gelatin capsules and with oral antiemetics. The pharmacokinetics of platinum were studied on days 1 and 5 of the first treatment course using atomic absorption spectrophotometry (AAS).

RESULTS

Thirty-two patients received 94 courses of oral JM216 at doses that ranged from 30 to 140 mg/m2 body-surface area for 5 consecutive days. The MTD was 140 mg/m2/d. The dose-limiting toxicities were thrombocytopenia and neutropenia. Hematotoxicity was reversible (nadir, 17 to 21 days; recovery, 28 days), noncumulative, and dependent on the dose and history of previous therapy. There were two instances of neutropenic sepsis. Two-thirds of patients experienced mild nausea, vomiting, or diarrhea. There was no ototoxicity, neurotoxicity, nephrotoxicity, or objective tumor responses. There was a significant correlation between JM216 dose and the day 1 and 5 plasma ultrafiltrate area under the concentration-time curve (AUC; r = .78), which indicates linear pharmacokinetics. There was considerable intersubject pharmacokinetic and pharmacodynamic variability, but a significant sigmoidal relationship between the plasma ultrafiltrate AUC and severity of thrombocytopenia (R2 = .83).

CONCLUSION

We recommend JM216 doses of 100 and 120 mg/m2/d x 5 for previously treated and untreated patients, respectively, for phase II trials.

A phase I and pharmacology study of an oral platinum complex, JM216: dose-dependent pharmacokinetics with single-dose administration

JM216 [bis-acetato-ammine-dichloro-cyclo-hexylamine-platinum (IV)] is an oral platinum complex with in vivo activity against murine and human tumor models and a lack of nephro- and neurotoxicity in rodents. During a phase I study of a single-dose schedule, JM216 was given in dry-filled hard gelatin capsules by mouth without hydration or diuresis. In all, 37 patients were given a total of 88 courses at doses ranging from 60 to 700 mg/m2. The study was stopped before the MTD was reached because of nonlinear pharmacokinetics. Myelosuppression was manifest by leucopenia or thrombocytopenia and showed marked variability at 420-700 mg/m2. Vomiting was mild and controllable by antiemetics in approximately 50% of courses. The onset of vomiting was delayed to 4 h after during ingestion. There was no nephro-, oto- or neuro-toxicity. A partial response was recorded in a patient with recurrent ovarian cancer, and significant falls in plasma tumour markers (CA125) were seen in two further cases. Plasma pharmacokinetics were linear and showed moderate interpatient variability at dose levels of < or = 120 mg/m2. At dose levels of > or = 200 mg/m2, Cmax and AUC increased less than proportionally to dose. This was associated with greater interpatient pharmacokinetic variability and reduced urinary platinum recovery. A significant sigmoidal relationship existed between ultrafilterable plasma AUC and the percentage of reduction in platelet count (r2 = 0.78). Nonlinear absorption was a limitation to this single-dose schedule of oral NM216; however, little non-haematological toxicity was seen at doses associated with myelosuppression and antitumour activity. Clinical studies of divided dose schedules using doses within the range of pharmacokinetic linearity (< or = 120 mg/m2) are now being investigated.