The phrase "are derived not" is correct and usable in written English.
It can be used in contexts where you want to emphasize that something does not come from a particular source or origin.
Example: "The conclusions of this study are derived not from anecdotal evidence, but from rigorous scientific research."
Alternatives: "do not originate from" or "are not sourced from".
As when he led Operation Rescue, his assumptions are derived not from compassion but from anti-choice extremism, with disregard for the privacy of families struggling to make extremely difficult decisions.
The refractive system of the eye and, in particular, the lens of the eye are derived not from the cup but from the epidermis overlying the eye rudiment.
Some genuine, if mild, laughs are derived not by subverting talk-show clichés but simply by compressing them: a one-joke stand-up routine, a bumped guest nearly every episode.
He emphasized that the new numbers may not reflect the true incidence of the syndrome because they are derived not from clinical exams but from descriptive reports provided by teachers and others, which were reviewed by experts for key words that suggested a diagnosis of autism, Asperger syndrome or any of several related disorders.
GDEC's affordances, however, are derived not solely from the Google Drive technology but also from the theoretical and pedagogical foundations of collaboration and scaffolding.
To begin, political opportunities are derived not only from structural changes but also from the signals that political systems emit (Meyer and Minkoff 2004).
Freud's vision of human psychology is derived, not altogether unconsciously, from his reading of Shakespeare's plays.
But the authorities said the contaminant was ground-up castor beans, from which ricin is derived, not the purified form of the toxin, which is far deadlier.
2). We need better intelligence, the kind that is derived not from intercepting a president's phone calls to his mistress but from hanging out with the powerless.
It is worth mentioning that the discussed results have been derived not only with simulation/analysis but also with measurements coming from a testbed implementation.
When an important photograph or other work of art is purchased, we must be prepared to admit that most of its market value is derived not from the visible work but from its invisible associations.
