Iraffinity 1 ftir

Chemicals were obtained from Sigma Aldrich. Reaction progress was monitored by thin layer chromatography (TLC) using silica gel plates and chloroform:methanol (9:1) as the eluent. Melting points (mp) were determined on a Buchi B-540 capillary melting point apparatus in open capillaries and uncorrected. IR spectra were recorded in KBr discs on a Shimadzu IR Affinity-1 FTIR. 1 H NMR (DMSO-d 6 ) spectra were run on a
Varian MERCURY 400 MHZ and 13 C NMR (APT) (DMSO-d 6 ) spectra were run Bruker 500 MHz spectrophotometers. Microanalyses were performed on a Thermo Finnigan Flash EA 1112 elemental analyzer.
(Sp: spirothiazolidinone, Ar: aromatic ring).

An IR spectrophotometer equipped with Shimadzu IR Affinity-1 FT-IR (Shimadzu, Japan) was used to study the interaction between the drug and the ENV system to determine the influence of the vesicle membrane component on the drug. When a drug interacts with the compounds in the NV system, the IR spectrum of the physical mixture corresponding to the drug exhibits additional peaks or does not contain characteristic peaks (Ţucureanu et al. 2016) . The FT-IR peaks from 400 cm -1 to 4000 cm -1 were assessed to find any additional or missing peaks from the fingerprint and the functional region (Arkin 2013).

Unless otherwise specified, all reagents and starting materials were of reagent grade or better and purchased from standard suppliers and used as received. Water was purified by reverse osmosis. Where anhydrous solvents were required, HPLCgrade solvent was either distilled from standard drying agents or dried by passing over a sealed column of activated alumina.
Powder X-ray diffraction patterns were obtained using a GBC-MMA diffractometer operating at 1.0 kW with samples mounted on 1" quartz substrates. Simultaneous thermogravimetric-differential thermal analysis (TG-DTA) traces were obtained using a Shimadzu DTG-60 instrument fitted with a FC-60A flow rate controller and TA-60WS thermal analyser using measuring parameters of 10 °C per min under nitrogen flow of 20 cm 3 min -1 . Infrared spectra were obtained using a Shimadzu IR Affinity-1 FTIR, fitted with a MIRacle 10 single reflection ATR accessory. Microanalyses were recorded by Mr Alan Carver (University of Bath Microanalysis Service) or Gillian Maxwell (University College London Microanalysis Service) or the Microanalytical Unit, Australian National University, Australia or the Campbell Microanalytical Laboratory, University of Otago, New Zealand.