Methyl Sulfate - Negative- Equivocal
Compound name: Methyl Sulfate
Molecular formula: CH4O4S
Average mass: 112.105
SMILES formula: S(=O)(=O)(O)OC
In Silico Assessment
The compound was assessed using the ICH M7 functionality in Nexus (v2.1) which contains the expert rule-based system Derek Nexus (v5.0) and the statistical-based system Sarah Nexus (v2.0). The following predictions were observed:
Mapping this onto Lhasa's Decision Matrix:
Conservatively could assign as positive. May conclude negative if strong evidence showing feature driving a 'no prediction' is present in the same context in known negative examples (without deactivating features).
The following prediction details were gathered:
- Derek Nexus – Inactive with no misclassified or unclassified features.
- Sarah Nexus – Equivocal prediction with examples which chiefly show dialkyl sulphates as positive but monoalkyl sulphates as negative.
The following is an expert assessment on the evidence gathered:
- No alerts fired.
- The lack of misclassified features shows that none of the features of this compound were found to be in non-alerting mutagens in the Lhasa Ames Test reference set.
- The inactive prediction also outlines the lack of unclassified features. This demonstrates that all features of the compound were found in the Lhasa Ames Test reference set.
- The compound is predicted to be equivocal. The compound is in the domain of the model, however no local hypotheses have been identified.
- A prediction has been made based on the activity of the 8 most similar examples from the training set.
Having reviewed the prediction details (and the predictions for analogues), the following call has been suggested:
Negative – Derek Nexus made a confident negative prediction. Sarah Nexus returned an equivocal prediction using the 8 most similar compounds from its training set. The compounds closest in similarity to the query compound have a negative outcome, so there is reasonable evidence to suggest that methyl sulfate has a negative outcome. An expert would also comment that mechanistically monoalkyl sulphates are not nucleophilic. This is sufficient evidence to provide an overall call of negative.