Results with the
methylenedioxy derivatives of cathinone are quite interesting.
The cathinone counterpart, 3,4-methylenedioxycathinone or
MDC, failed to completely substitute for (1)amphetamine or
DOM (Tables 1 and 2). Thus, introduction of the carbonyl
group has changed the properties of the molecule so that it no
longer seems to function in the same manner as its parent (i.e.,
MDA). This represents a qualitative divergence in the structure–
activity relationships of amphetamine and cathinone.
The N-monomethyl derivative of MDA, MDMA, possesses
amphetamine-like character but lacks DOM-like properties
(10). N-Monomethylation of MDC affords an agent,
MDMC, that behaves in a similar fashion. That is, a (1)amphetamine
stimulus (Table 1), but not a DOM stimulus (Table
2), generalized to MDMC. In terms of amphetamine-like
activity, MDMC (ED50 5 10.1 mmol/kg) is similar in potency
to MDMA (ED50 5 7.5 mmol/kg) (Table 3). In this instance
then, the effect of introducing the carbonyl oxygen was simply
to slightly reduce amphetamine-like potency.
From the foregoing discussion it would seem that MDC no
longer behaves like MDA but that MDMC retains the amphetamine-
like character of MDMA. Interestingly, both
MDC and MDMC retain MDMA-like character (Table 2) in
that they completely substituted for MDMA (i.e., they produced
.80% MDMA-appropriate responding) in MDMA-trained
rats. Because MDMC (ED50 5 1.6 mg/kg; 6.9 mmol/kg) was
about half as potent as MDMA itself (ED50 5 0.76 mg/kg;
3.5 mmol/kg) (12), it would seem that here, too, the effect of
carbonyl-oxygen introduction is to decrease potency
