Heterolytic fragmentation is widespread and serves as a useful reaction in organic synthesis. 1 We have previously reported 2 that an unusual heterocyclic fragmentation reaction occurs in the hydride reduction of N-methoxymethylpyrrolo[2,1-c][1,4]benzodiazepine-5,11diones, synthetic intermediates to a family of anticancer DNA alkylating agents known as pyrrolo[2,1-c]benzodiazepines. We postulated that this reaction proceeds via 3-aza-Grob fragmentation 3-9 as shown in Scheme 1.We recently extended our studies to ether-protected aromatic lactams with five-and six-membered rings. The results showed that hydride reduction of MOM-, MEM-, SEM-, and BOM-protected oxindole analogues gave ringopening products via the same path as seven-membered ring lactams, N-methoxymethylpyrrolo [2,1-c][1,4]benzodiazepine-5,11-diones, in excellent yields. 10

Mongoloid populations differ from Caucasoids by having a high prevalence of shovel trait and a low prevalence of Carabelli's trait. This study was conducted to investigate the effects of the shovel trait on Carabelli's trait in a Mongoloid population. The research design sought a population that resides in an isolated area and exhibits low admixture with neighboring populations. The Mongoloid group selected for study was the Bunun tribe of aborigines who inhabit an alpine area in Taiwan. The effects of sex and age on Carabelli's trait were controlled in this investigation, as was the association between tooth size and Carabelli's trait. Results show that males were more likely to have Carabelli's trait expressed on teeth than females. The buccolingual diameter of Carabelli's trait teeth was larger than that of teeth without the trait. After adjusting for sex, age, and tooth size, the existence of the shovel trait increased the likelihood of having Carabelli's trait by a factor of three, an effect that is significant.

Borane reduction of ether-protected aromatic lactams produces 1-alkyl-1,2,3,4-tetrahydroquinolines (5 and 6) in excellent yields. This reaction provides a novel one-pot tandem process for reduction of amide group and N-protected groups. Experimental results demonstrate that the reaction proceeds through two consecutive elimination and reductions via two C-O bond cleavages to form the foresaid products.

Quinoline derivatives Quinoline derivatives R 0410Novel Borane Reduction of Ether-Protected Aromatic Lactams. -The borane-mediated reduction of the ether-protected lactams (I) and (III) leads to N-methyl-1,2,3,4-tetrahydroquinoline via a novel one-pot tandem process including two consecutive eliminations and reductions. The lactams (IV) containing cyclic ethers give the ring opening products (V). -(HU, W.-P.; TSAI, P.-C.; HSU, M.-K.; WANG*,