5'-O-(p,p'-dimethoxytrityl)thymidine

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-09-19 to 2018-02-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling Point)

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

GLP compliance:

no

Type of method:

differential scanning calorimetry

Key result

Atm. press.:

1 013.3 hPa

Decomposition:

yes

Decomp. temp.:

ca. 240 °C

The first DSC measurement with a heating rate of 10 K/min up to a temperature of 500 °C showed an endothermal effect in the temperature range of 130 °C - 170 °C. At approximately 240 °C a slight exothermal effect begins and decomposition takes place. The decomposition of the substance was confirmed by the appearance of the sample after measurement (black residue) combined with a mass loss of 87% of the initial weigh-in.

A second DSC measurement under the same conditions but only up to a temperature of 200 °C showed an endothermal effect (melting) in the temperature range of 130 °C - 160 °C. After the second measurement the test item was a yellow melt in the crucible and no mass loss was observed. Hence, no additional endothermal effects were observed after the first one between 130 °C - 160 °C and before the exothermal effect starting at approx. 240 °C. The observed exothermal effect indicated a decomposition of 5’-O-(4,4’-Dimethoxytrityl)thymidine and therefore no boiling point could be determined. The test item has no boiling point under atmospheric conditions.

Conclusions:

The observed exothermal effect at a temperature of approx. 240 °C indicated the decompostion of the substance 5’-O-(4,4’-Dimethoxytrityl)thymidine. The test item has no boiling point under atmospheric conditions.

Executive summary:

The boiling point / boiling range of the test item 5’-O-(4,4’-Dimethoxytrityl)thymidine was investigated by DSC measurement according to OECD 103. The study showed that the test item starts to decompose at a temperature of approx. 240 °C indicated by an exothermal effect. No boiling point could be determinend before decomposition. The test item 5’-O-(4,4’-Dimethoxytrityl)thymidine has no boiling point under atmospheric conditions.

Description of key information

The boiling point / boiling range of the test item 5’-O-(4,4’-Dimethoxytrityl)thymidine was investigated by DSC measurement according to OECD 103. The study showed that the test item starts to decompose at a temperature of approx. 240 °C indicated by an exothermal effect. No boiling point could be determinend before decomposition. The test item 5’-O-(4,4’-Dimethoxytrityl)thymidine has no boiling point under atmospheric conditions.