Daily digest — 2026-09-22

First reaction: that's a nifedipine scaffold sitting in a caspase-1 SAR table. Bold, slightly nervy move — DHPs are about as pharmacologically 'loaded' as chemotypes get, so before getting excited about any hit here I'd want an L-type calcium-channel counter-screen and a broader Cav/hERG panel run immediately; that vasodilatory liability doesn't vanish just because you've redirected the scaffold at a protease. Caspase-1 itself is a reasonable target — druggable active-site cysteine, real precedent from peptidomimetic inhibitors — but selectivity across the caspase family, not potency, is the real hurdle here. The fluorescence assay plus cell imaging is the right combo methodologically: biochemical IC50s alone can't distinguish real antagonism from aggregation, chelation, or off-target channel hits, so imaging buys an early cellular engagement check before committing to a full selectivity panel.

- The real headline isn't the potency bump — it's that the PIP-box pocket, a shallow PPI interface people wrote off as undruggable, actually supports systematic SAR across four independent pharmacophore regions. That's a proper chemotype, not a lucky HTS hit. - Getting better cellular potency AND better microsomal stability out of substituent/bioisostere/linker/scaffold-hop work is the signal I want at this stage — potency alone would leave me wondering if you'd just traded one metabolic liability for another. - "Selective for caPCNA" is a claim I'll hold loosely until I see a real therapeutic index — normal-cell counterscreens and in vivo tox, not just cancer-line IC50s. The acidic-isoform story is attractive but easy to oversell. - Still, beating first-gen AOH1996 on both axes is the right trajectory for a second-gen PPI series.

CK1δ/α/ε selectivity is the real fight here — those kinase domains are similar enough that classic ATP-competitive chemistry rarely holds up cleanly; if they're threading that needle with a degrader, ternary-complex geometry, not just binary affinity, is probably doing the selectivity work, which is the whole pitch for going bifunctional over yet another inhibitor. Smart use of event-driven pharmacology to reach something genuinely undruggable — NRAS has no covalent handle like G12C, so knocking down an upstream stabilizer is a legitimate end-run, not a gimmick. Still want to see the actual chemotype and E3 handle before getting excited — 'synthesized series, iterative SAR' tells me nothing about scaffold novelty or synthetic cost, and degrading a kinase with this many substrates makes me nervous about toxicity beyond the CK1α story. If selectivity and PK hold up in vivo, this is a template worth stealing for other 'stabilizer' targets propping up undruggable oncoproteins.

Single scaffold, two GPCR pharmacophores, no PK penalty — that's the hard part, not the target rationale. Anyone who's tried to graft an M3 antagonist pharmacophore onto an H1 chemotype knows the tightrope: push affinity at one receptor and you drag the other's SAR along for the ride, or worse, the two optimize in opposite directions on logP/basicity. If they actually held balanced dual potency while stretching half-life toward once-daily dosing, that's real design work, not a screening accident. Target rationale is the more interesting sell, though — mixed/nonallergic rhinitis genuinely doesn't respond well to a single mechanism, so this isn't a me-too antihistamine with a longer half-life. Show me the selectivity margins before I get excited: M3 hits M2/M1 too easily, and dry mouth/blurred vision/urinary retention kill programs late. Therapeutic window on the anticholinergic side is the whole ballgame here.

Holding balanced dual-target SAR on one scaffold is the real difficulty here, not the headline claim — PARP-1's nicotinamide pocket and CK2α's ATP site are shaped nothing alike, so a substituent you add to hold potency at one target can quietly tank the other. I'd want the full SAR table, not just the lead actives, before believing that balance survives further optimization. The real payoff isn't PARP-1 potency itself, it's escaping the BRCA/HRD ceiling — another single-target PARP inhibitor chasing olaparib's lane is a hard sell, but HRD-independent activity actually opens new patient populations. The tricyclic benzothienopyrimidinone core gives usable vectors for dual substitution, though fusing two pharmacophores tends to inflate MW and logP fast. Next data I need: kinome-wide selectivity beyond CK2α, in vivo therapeutic window, and whether the anti-metastatic signal holds up against a PARP-1-only comparator.