Adenosine

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 October 2017 - 12 January 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

from 27 July 1995

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7200 (Melting Point / Melting Range)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Test material

Test material information

Constituent 1

Reference substance name:

Adenosine

EC Number:

200-389-9

EC Name:

Adenosine

Cas Number:

58-61-7

Molecular formula:

C10H13N5O4

IUPAC Name:

adenosine

impurity 1

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Oxidane

Test material form:

solid: particulate/powder

Details on test material:

Batch No.: 10004539
Storage at room temperature approx. 20°C

Results and discussion

Melting / freezing point

Key result

Melting / freezing pt.:

235.5 °C

Atm. press.:

>= 1 014 - <= 1 016 hPa

Decomposition:

yes

Decomp. temp.:

ca. 250 °C

Any other information on results incl. tables

In the temperature range of 230 – 250 °C, an endothermic effect was observed, which can be assigned to the melting of the test item. The endothermic effect was directly followed by an exothermic effect in the temperature range of 250 – 300 °C, with an average decomposition energy of -220 J/g. No further thermal effects were observed up to the test end temperature of 500 °C. As the onset temperatures in both tests do not deviate by more than 0.5 K from their mean value of 235.53 °C, this temperature can be used as melting point. The test item has a melting point of 235.5 °C accompanied by decomposition.

No.	Sample weight (mg)	Onset of effect (°C)	Range of effect (°C)	Weight loss (mg)	Atmospheric pressure (hPa)
1	9.62	235.58 250	230 - 250 (endo) 250 - 300 (exo)	4.78	1016.1
2	12.01	235.47 250	230 - 250 (endo) 250 - 300 (exo)	6.64	1014.2

To verify the results of the DSC measurement, two additional measurements with the capillary method (Apparatus: Stuart Melting Point SMP30) were performed in the temperature range of 150 – 350 °C with a heating rate of 10 K/min. According to the observations during the test with the capillary method, the first endothermic effect in the temperature range of 230 – 250°C in the DSC measurements can be assigned to the melting of the test item, which is directly followed by its decomposition. The test item changed its colour from white to black starting at a temperature of approx. 260 °C and expands throughout the capillary.

Applicant's summary and conclusion

Conclusions:

The test item Adenosine (CAS no. 58-61-7) has a melting point of 235.5 °C accompanied by its decomposition starting at a temperature of approx. 250 °C at atmospheric pressure (1014 –1016 hPa) as determined by differential scanning calorimetry according to Regulation EC No. 440/2008 Method A.1. and OECD Test Guideline 102 (1995).

Executive summary:

The test item Adenosine (CAS no. 58-61-7) has a melting point of 235.5 °C accompanied by its decomposition starting at a temperature of approx. 250 °C at atmospheric pressure (1014 –1016 hPa) as determined by differential scanning calorimetry according to Regulation EC No. 440/2008 Method A.1. and OECD Test Guideline 102 (1995).