Ambara R. Pradipta 교수

Clean surgical margins in breast-conserving surgery (BCS) are essential for preventing recurrence. Intraoperative pathologic diagnostic methods, such as frozen section analysis and imprint cytology, have been recognized as crucial tools in BCS. However, the complexity and time-consuming nature of these pathologic procedures still inhibit their broader applicability worldwide. To address this situation, two issues should be considered: 1) the development of nonpathologic intraoperative diagnosis

Acrolein, a highly toxic α,β-unsaturated aldehyde, has been a longstanding key biomarker associated with a range of disorders related to oxidative stresses. Currently available analytical methods rely on the indirect protocols, e.g., derivatization/HPLC or mAb detection of the lysine adducts. Consequently, developing new analytical tools for acrolein detection that are straightforward, cost-effective, selective, and preferably feasible using live cells remains a highly essential pursuit in the d

Cytotoxic anticancer drugs used in chemotherapy are often antiproliferative agents that preferentially kill rapidly growing cancer cells. Their mechanism relies mainly on the enhanced proliferation rate of cancer cells and is not genuinely selective for cancer cells. Therefore, these drugs can also significantly affect healthy cells. Prodrug therapy provides an alternative approach using a less cytotoxic form of anticancer drug. It involves the synthesis of inactive drug derivatives which are co

Abstract Imines are among the most ubiquitous species in organic and bioorganic chemistry; however, the reactivities of N-alkyl unsaturated imines have not been thoroughly explored due to their instability profiles. Here, we describe the novel reactivity of N-alkyl unsaturated imines derived from substituted aldehydes, a chiral aminoalcohol, and paraformaldehyde to produce hexahydropyrimidines and 1,3,5-triazacyclooctanes through a formal asymmetric [4+2] and [4+2+2] cycloaddition reaction in a

Hydroxyl groups on an unsaturated imine, which may be readily obtained from the corresponding unsaturated aldehyde and the 1,2-ethanolamine derivative, were found to efficiently activate a [4+4] dimerization reaction to produce the eight-membered 1,5-diazacyclooctane. A novel OH–π interaction between the two imines, in addition to the stabilization of the eight-membered diacetals, was proposed based on density functional theory calculations.

Nucleotide-binding oligomerization domain protein 1 (Nod1) is an intracellular protein involved in recognition of the bacterial component peptidoglycan. This recognition event induces a host defense response to eliminate invading pathogens. The genetic variation of Nod1 has been linked to several inflammatory diseases and allergies, which are strongly affected by environmental factors. We have found that many of the bacteria that contain DAP-type peptidoglycan release Nod1 ligands into the envir

Abstract Recently, we found that a bulky 2,6-diisopropylphenyl azide is more reactive than a simple phenyl azide toward acrolein. Herein, we conjugated tetramethylrhodamine (TAMRA) to the bulky phenyl azide and utilized it as a second-generation click-to-sense (CTS) probe to analyze cancer by targeting the cellular acrolein. Subsequently, we observed that this second-generation CTS probe could distinguish breast cancer tissues with higher sensitivity than the first-generation CTS probe. Moreover

Targeted α-particle therapy (TAT) is an attractive alternative to conventional therapy for cancer treatment. Among the available radionuclides considered for TAT, astatine-211 (²¹¹At) attached to a cancer-targeting molecule appears very promising. Previously, we demonstrated that aryl azide derivatives could react selectively with the endogenous acrolein generated by cancer cells to give a diazo compound, which subsequently forms a covalent bond with the organelle of cancer cells <i>i

Acrolein holds excellent potential as a biomarker in various oxidative stress-related diseases, including cancer, Alzheimer's, Parkinson's, and inflammatory disorders. Consequently, a direct method to target and visualize acrolein in biological systems might be essential to provide tools for diagnosis and therapeutic purposes. Previously, we discovered 1,3-dipolar cycloaddition between aryl azides and acrolein, which proceeds without a catalyst to give α-diazocarbonyl derivatives. The reaction p

Cells are covered with a thick layer of sugar molecules known as glycans. Abnormal glycosylation is a hallmark of cancer, and hypersialylation increases tumor metastasis by promoting immune evasion and inducing tumor cell invasion and migration. Inhibiting sialylation is thus a potential anticancer treatment strategy. However, targeting sialic acids is difficult because of the lack of selective delivery tools. Here, we present a prodrug strategy for selectively releasing the global inhibitor of

The chiral substituted 1,5-diazacyclooctane (1,5-DACO) is of considerable importance and has attracted attention from a wide range of fields due to their unique chemical and biological properties. Despite the application potential, further study has not been optimized due to difficulties in their synthetic accessibility. Here, we report that the 1,5-DACO bearing a chiral auxiliary obtained from the formal [4+4] cycloaddition of N-alkyl-α,β-unsaturated imines can be further derivatized by nucleop

N-alkyl unsaturated imines derived from acrolein, a toxin produced during oxidative stress, and biogenic alkyl amines occur naturally and are considered biologically relevant compounds. However, despite the recent conceptual and technological advances in organic synthesis, research on the new reactivity of these compounds is lacking. This personal account discusses research on the reactivity that has been overlooked in acrolein imines, including the discovery of new methods to synthesize biologi

Imines are among the most ubiquitous species in organic and bioorganic chemistry; however, the reactivities of N-alkyl unsaturated imines have not been thoroughly explored due to their instability profiles. We describe the novel reactivity of the N-alkyl-unsaturated imines derived from substituted aldehydes, aminoalcohol or diamine, and paraformaldehyde to produce 2,6,9-triazabicyclo [3.3.1] nonanes, 1,5-diazacyclooctanes, hexahydropyrimidines and 1,3,5-triazacyclooctanes through a formal [4+4],