A number of ethyl 4-(2-benzylalkyloxy)benzoates were prepared and their activity to induce precocious metamorphosis was evaluated in larvae of the silkworm, Bombyx mori, which was clearly recognized as a juvenile hormone (JH)-deficiency symptom. Ethyl 4-(2-benzylhexyloxy)benzoate (6) and its 2-benzylheptyloxy analog (7) were found to induce precocious metamorphosis at relatively low doses. Both enantiomers of 6 and 7 were prepared using a chiral auxiliary oxazolidinone. (S)-Enatiomers were more active than (R)-isomers at low doses of 0.1 and 1 mg, but at higher doses their activity was reversed. The activity of compound 6 could be fully counteracted by methoprene, a JH agonist, but not by the dietary administration of 20-hydroxyecdysone. The ester group was important in the ability to induce precocious metamorphosis. The (S)-enatiomer of 6 prolonged the duration of the instar and delayed the onset of cocoon spinning when applied to 5th instar larvae, suggesting that this compound might have JH-like activity as well as anti-JH activity.

No abstract

As a new alternative to antibody-drug conjugates, we generated “ligand-targeting” peptide-drug conjugates (PDCs), which utilize receptor-mediated endocytosis for targeted intracellular drug delivery. The PDC makes a complex with an extracellular ligand and then binds to the receptor on the cell surface to stimulate intracellular uptake via the endocytic pathway. A helix-loop-helix (HLH) peptide was designed as the drug carrier and randomized to give a conformationally constrained peptide library. The phage-displayed library was screened against vascular endothelial growth factor (VEGF) to yield the binding peptide M49, which exhibited strong binding affinity (KD = 0.87 nM). The confocal fluorescence microscopy revealed that peptide M49 formed a ternary complex with VEGF and its receptor, which was then internalized into human umbilical vein endothelial cells (HUVECs) via VEGF receptor-mediated endocytosis. The backbone-cyclized peptide M49K was conjugated with a drug, monomethyl auristatin E, to afford a PDC, which inhibited VEGF-induced HUVEC proliferation. HLH peptides and their PDCs have great potential as a new modality for targeted molecular therapy.

Opioid-induced-constipation (OIC) can be treated by naldemedine and other peripherally acting mu-opioid receptor antagonists (PAMORA) via a novel mechanism. We describe the case of a 52-year-old female outpatient who developed OIC while receiving oxycodone for pain due to cancer with multiple bone metastases. Although she did not have brain metastasis, opioid withdrawal syndrome (OWS) developed after taking naldemedine orally. Her Clinical Opiate-Withdrawal Score (COWS) was 19 (moderate symptoms). However, she recovered from OWS on intravenous fentanyl and a continuous infusion of oxycodone. She did not develop OWS thereafter and was discharged two days after recovery.