Diberal, also known as 5-(1,3-Dimethylbutyl)-5-ethylbarbituric acid or DMBB, is an atypical

barbiturate Barbiturates are a class of depressant drugs that are chemically derived from barbituric acid. They are effective when used medically as anxiolytics, hypnotics, and anticonvulsants, but have physical and psychological addiction potential as we ...

. This compound can be either

convulsant A convulsant is a drug which induces convulsions and/or epileptic seizures, the opposite of an anticonvulsant. These drugs generally act as stimulants at low doses, but are not used for this purpose due to the risk of convulsions and consequent exc ...

anticonvulsant Anticonvulsants (also known as antiepileptic drugs or recently as antiseizure drugs) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of b ...

depending on which enantiomer is used.

Pharmacology

Diberal, unlike most

s, can have convulsant actions. This is uncommon, as barbiturates typically enhance the function of GABA as allorestic modulators and

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...

s (at higher doses), therefore having

properties. Depending on which isomer is used, it can have either

or anticonvulsant actions. The different pharmacological profile between

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

s is thought to be due to the differences in the formation of

hydrogen bond In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a ...

s at the binding sites.

(+)-Isomer

(+)-DMBB is the atypical enantiomer of diberal. It is atypical in the means that it has convulsant action, unlike most barbiturate drugs.

(−)-Isomer

Unlike (+)-DMBB, the (−)-isomer is similar to most barbiturates by having anticonvulsant action. It has been found that administration of (−)-DMBB reverses the convulsant actions of (+)-DMBB. (−)-DMBB is slightly more potent than

pentobarbital Pentobarbital (previously known as pentobarbitone in Britain and Australia) is a short-acting barbiturate typically used as a sedative, a preanesthetic, and to control convulsions in emergencies. It can also be used for short-term treatment of ...

in its depressant properties.

References

{{Convulsants Convulsant barbiturates