An unprecedented copper-catalyzed intramolecular radical cyclization was developed for the synthesis of 3-hydroxypyrroloindoline skeletons in excellent yields. The 3-hydroxyl group was introduced by trapping the radical intermediate with molecular oxygen or TEMPO. This process represents a unique radical oxidation pathway for tryptamine/tryptophan derivatives and allows a rapid biomimetic synthesis of natural product protubonine A.
A facile and straightforward method was developed to construct the fused tetracyclic 3-spirooxindole skeleton, which exists widely in natural products. The formation of the tetracyclic 3-spirooxindole structure was achieved through a transition-metal-free intramolecular cross-dehydrogenative coupling of pyridinium, which were formed in situ by the condensation of 3-(2-bromoethyl)indolin-2-one derivatives with 3-substituted pyridines. As examples of the application of this new methodology, two potentially medicinal natural products, (±)-corynoxine and (±)-corynoxine B, were efficiently synthesized in five scalable steps.
A Curtius-like rearrangement of hydroxamates to isocyanates was discovered. This reaction was initiated from an iron(II)-nitrenoid complex, which was generated by the iron(II)-catalyzed cleavage of N-O bonds of functionalized hydroxamates. To demonstrate the efficiency of this new Curtius-like rearrangement in synthetic chemistry, a biomimetic strategy for the one-pot preparation of bisindolylmethanes was developed.
A copper-mediated cyclization and dimerization of tryptamine or tryptophan was developed to generate a C2-symmetry C3(sp(3))-C3(sp(3)) bridge with two contiguous stereogenic quaternary carbons in one step. Impressively, the ratio between exo and endo cyclization products varies when different protecting groups of Nb are utilized. This dimerization reaction could be conducted in gram scale. With this dimerization method, both endocyclotryptophan (+)-WIN 64821 and exocyclotryptophan (-)-ditryptophenaline were synthesized in 5 steps.
Anti-CD30 CAR-T is a potent candidate therapy for relapsed/refractory (r/r) CD30+ lymphomas with therapy limitations, and the efficacy needed to be further improved. Herein a multi-center phase II clinical trial (NCT03196830) of anti-CD30 CAR-T treatment combined with PD-1 inhibitor in r/r CD30+ lymphoma was conducted. After a lymphocyte-depleting chemotherapy with fludarabine and cyclophosphamide, 4 patients in cohort 1 and 3 patients in cohort 2 received 106/kg and 107/kg CAR-T cells, respectively, and 5 patients in cohort 3 received 107/kg CAR-T cells combined with anti-PD-1 antibody. The safety and the efficacy of CAR-T cell therapy were analyzed. Cytokine release syndrome (CRS) was observed in 4 of 12 patients, and only 1 patient (patient 9) experienced grade 3 CRS and was treated with glucocorticoid and tocilizumab. No CAR-T-related encephalopathy syndrome was observed. Only two patients in cohorts 2 and 3 experienced obviously high plasma levels of IL-6 and ferritin after CD30 CAR-T cell infusion. The overall response rate (ORR) was 91.7% (11/12), with 6 patients achieving complete remission (CR) (50%). In cohorts 1 and 2, 6 patients got a response (85.7%), with 2 patients achieving CR (28.6%). In cohort 3, 100% ORR and 80% CR were obtained in 5 patients without ≥3 grade CRS. With a median follow-up of 21.5 months (range: 3-50 months), the progression-free survival and the overall survival rates were 45 and 70%, respectively. Of the 11 patients who got a response after CAR-T therapy, 7 patients (63.6%) maintained their response until the end of follow-up. Three patients died last because of disease progression. Taken together, the combination of anti-PD-1 antibody showed an enhancement effect on CD30 CAR-T therapy in r/r CD30+ lymphoma patients with minimal toxicities.
Immunonutritional status is associated with the survival of DLBCL. This multicenter retrospective study aimed to explore the prognostic value of Prognostic Nutrition Index (PNI) in DLBCL patients by using propensity score matched analysis (PSM). Methods: A total of 990 DLBCL cases were recruited from 5 centers of Huaihai Lymphoma Working Group (HHLWG). A 1:1 PSM analysis was performed using the nearest-neighbor method, with a caliper size of 0.02. Cox regression analysis was used to examine factors associated with survival.
Results:The median age at diagnosis was 62 years and 52.5% were males, with the 3-y overall survival of 65.1%. According to the MaxStat analysis, 44 was the optimal cutoff point of PNI. After PSM analysis, a total of 282 patients in PNI < 44 group could be propensity matched to PNI ≥ 44 patients, creating a group of 564 patients. Multivariable analysis revealed that PNI, age, central nervous system involvement and International Prognostic Index (IPI) were independent prognostic factors for DLBCL. Kaplan-Meier analysis indicated that patients with low PNI in Ann Arbor Stage (III/VI), ECOG (<2), IPI (LR+LIR), GCB, and BCL-2 negative groups had a poor prognosis. Discussion: PNI could accurately stratify the prognosis of DLBCL after PSM analysis.
Based on a modified coupled wave theory, the pulse shaping properties of volume holographic gratings (VHGs) in anisotropic media VHGs are studied systematically. Taking photorefractive LiNbO(3) crystals as an example, the combined effect that the grating parameters, the dispersion and optical anisotropy of the crystal, the pulse width, and the polarization state of the input ultrashort pulsed beam (UPB) have on the pulse shaping properties are considered when the input UPB with arbitrary polarization state propagates through the VHG. Under the combined effect, the diffraction bandwidth, pulse profiles of the diffracted and transmitted pulsed beams, and the total diffraction efficiency are shown. The studies indicate that the properties of the shaping of the o and e components of the input UPB in the crystal are greatly different; this difference can be used for pulse shaping applications.
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